27.上田城 その1

立地と歴史

上田城築城と第一次上田合戦

上田城を築いた真田昌幸(生年:1547年〜没年:1611年)は、真田幸隆(幸綱)の三男として生まれました。父親の幸隆は、信濃国真田郷の小豪族でしたが、武田信玄に仕え、重臣の一人となりました。特に調略を得意とし、後半生は武田氏の西上野での領土拡大に貢献しました(岩櫃城など)。昌幸は、当初信玄に近臣(武藤喜兵衛と名乗っていた)として仕え、信玄・幸隆が亡くなり、長篠の戦いで兄たち(信綱・昌輝)が討たれると、真田家を継ぎました。昌幸は、西上野の攻略を進め、1579年(天正7年)には沼田城を落としました。この城が、後の真田氏による領土経営のキースポットになります。彼は武田氏の一部将でしたが、一定程度の領土経営権を与えられていたと言われています。

やがて主君の武田氏が滅亡し、武田氏を滅ぼした織田信長が本能寺の変で討たれると、旧武田領(甲斐・信濃・西上野)は空白地帯となり、周辺有力大名(徳川・北条・上杉)による争奪戦が起こります(1982年(天正10年)の天正壬午の乱)。上田周辺から沼田までの一帯を勢力圏としていた昌幸は、有利な条件(領土維持)を求め、上杉→北条→徳川と、次々に傘下となる大名を変えていきます。当時、昌幸は山城の砥石城(またはその周辺の館)を本拠にしていたと考えられますが、徳川傘下にいたときに築いたのが上田城でした。上田の地は、徳川・上杉勢力圏の境目にあたり、街道(上州街道・北国脇往還)と千曲川が交わる地点で、徳川方として確保が必要な場所でした。つまりこの城は、徳川方が上杉方に対抗するために築かれたのです。従って、築城にあたっては、徳川方の全面支援があったと考えられています。平地での築城なので、上杉方からの妨害も受けやすく、築城時の安全確保の必要もありました(下記補足1)。

(補足1)海津よりの注進の如くんば、真田、海士淵(あまがふち)取り立つるの由に候条、追い払ふべきの由、何れへも申し遣はし候(天正十一年四月十三日島津左京亮宛上杉景勝書状「上杉年譜」)

平地の城であっても、自然の要害を生かして築かれました。城の南側は、千曲川の支流が流れ「尼ヶ淵」と呼ばれていて、切り立った崖になっていました。北や西から攻めてくる上杉方に対して、後ろ堅固の城であったと言えます。その北側と西側は、川(矢出沢川・蛭沢川)の流路を変え、元の流路を堀に活用し、新流路を惣堀として、備えとしました。城の中心部分は、かつて他の豪族(小泉氏)の城館として使われていた微高地を利用し、西から小泉曲輪・本丸・二の丸を並べました(梯郭式)。更に東側は沼沢地でしたが、その合間に昌幸や一族の屋敷地(中屋敷、常田屋敷、玄三屋敷)が作られました。築城は、1583年(天正11年)に始まり、2年後に完成したとされています。その頃の城の姿を表すとされる絵図(「天正年間上田古図」)が残されています。

ところが、昌幸は城が完成した時期に、徳川方から上杉方に鞍替えをします。これは、徳川家康が北条氏との和睦の条件として、沼田を北条氏に引き渡すと約束したことによります。替地も明確でなかったようです。昌幸はこれを拒否しました(下記補足2)。並みの地方領主だったら飲んだのでしょうが、昌幸は自分が切り取った領土にこだわったのです。上杉の支援があるとはいえ、北条(沼田への攻撃)・徳川双方を敵に回す決断でした。(ただし、上杉のバックにいた豊臣秀吉の存在を考慮したという指摘もあります)家康は激怒し、真田討伐を命じました(下記補足3)。これが第一次上田合戦です(天正13年7月〜11月)。

(補足2)
三河物語
ぬまた(沼田)を小田原(北条)へ渡せと仰せになったところ、さなだ(真田昌幸)は、ぬまたの城は上様よりいただいたものではなく、我らの手柄で取り立取った城なので筋違いの話です(訳:代替案のための弁証法的空間)

(補足3)敵幸ひの所へ引き出し候はば、この度根切り緊要に候(八月二十日徳川家康書状、「宮下家文書」)

鳥居元忠、大久保忠世らに率いられた約7千の徳川勢に対し、真田勢はわずか約1200人でした。しかも、上田城は対上杉用に築かれた城なので、東側(甲斐)から攻めてくる敵(徳川勢)は想定外でした。そのとき昌幸がとった戦術は、少ない兵を更に分散させて配置することでした。昌幸本人は上田城に、長男の信幸は砥石城に、残りを他の城や伏兵として布陣したのです。そして、敵の正面(東側)に対する防御はほぼ放置し、わざと攻めやすくさせたのです。徳川勢は、数は多いが寄せ集めで、真田勢を見下していたとも言われています。城の東側の神川を越え、中間の隘路(沼沢地)を通り、一気に二の丸まで攻め寄せました。この勢いで敵の統制が緩む隙をついて、真田勢は反撃に移り、砥石城の部隊も加わりました。徳川勢は退却しますが、真田勢の追撃を受け、神川で多くの兵士を失いました(1300人、下記補足4)。その後、徳川勢は攻め口を変えますが、戦線が膠着し、ついには撤退しました。この戦いは、真田の独立大名として道を開くとともに、その名を天下に知らしめました。昌幸だからこそできた離れ業と言えるでしょう。

(補足4)
沼田城重臣宛信幸返書
芳札披見、仍従遠州出張候間、去二日於国分寺遂一戦
千三百余討捕備存分に候、然者南衆(北条方)其表可相働候、
於然堅固之備憑入候 恐々謹言
閏八月十二日    真田源三郎  信幸 判
 下豊(下沼田豊前守)、恩伊(恩田伊賀守)、木甚、恩越、發参
去る二日国分寺において一戦を遂げ、千三百余り討ち取り、備へ存分に任せ候
芳しい書状を拝見した 遠州より徳川勢が攻めて来たが、去る2日国分寺に於いて一戦し、1300人余り討ち取り備えは十分である。そこで、北条方がそちらに攻めて来るに違いないので、堅固の備えを頼み入る(「恩田家文書」、訳:おぎはらの洋ラン日記)

豊臣大名の城に、そして第二次上田合戦

その後、昌幸が選んだ道は、豊臣秀吉への服従でした。秀吉は昌幸を「表裏比興の者(表と裏を使い分けるくせもの)」と呼び、一時討伐を決意しましたが許しました(下記補足5)。昌幸は、家康の与力大名となりますが、家康もまた、信幸を重臣の本多忠勝の娘(小松姫、形式上は家康の養女)の婿としたのです。こうして真田は豊臣政権下の大名となったのです。秀吉の天下統一の過程で、一時沼田城は北条のものとなりますが、小田原合戦の結果、真田の下に戻ってきました。

(補足5)
真田の事、先度この方において仰せ出し候如く、表裏比興の者に候間、成敗を加へらるべき旨仰せ出され候間、定めて家康人数相動くべく候条、その方より一切に見続等これあるまじきの由に候。(八月三日上杉景勝宛増田長盛・石田三成書状「上杉家記」)

天正十四年(一五八六)十一月二十一日付 真田昌幸宛羽柴秀吉書状(真田宝物館蔵)其の方事、家康存分これ有りと雖(いえど)も、此方(こなた)に於いて直(じき)に仰せ聞けられ候。殿下も曲事に思し召し候と雖も、此の度の儀は相免ぜられ候条、其の意を成し、早々罷り上るべく候。猶、様子仰せ含めらるべく候。委細尾藤左衛門尉申すべく候也。
   十一月二十一日(朱印)(羽柴秀吉)
     真田安房守とのへ
家康がお前を恨んでいる件については、自分から直接言い聞かせてやった、自分もけしからぬことだとは思うが、今度だけは許してやるので上洛するように(訳:秀吉と真田)

上田城は豊臣大名の城として、改修が進められました。第一次上田合戦のときには「殿守(天守)も無き小城」であったとされていますが、この改修で天守が建てられたのではないかとも言われています。現在の本丸堀などから、金箔瓦や鯱瓦が発掘されています。近隣で同様のものが使われた松本城・諏訪高島城・小諸城には天守がありました。また、江戸時代に作られた城の絵図(「上田城構之図」)には「御天守跡」という記載があります。一方で、金箔瓦は本丸以外(二の丸や小泉曲輪)でも発見されているので、天守以外で使われていたともいえます。また、天守があった可能性がある本丸北西隅には、石垣の痕跡がないことから、否定する向きもあります。天守があったとしても、三層程度だったであろうという意見もあります。いずれにせよ、初期とは全く違う豪華な櫓や門を備えた城になっていたとは言えるでしょう。また、弱点だった東側については、三の丸や大手門が整備され、城下町に寺町を作り、防御を固めたと考えられています。

そして秀吉が亡くなると、運命の天下分け目の戦い(1600年(慶長5年))を迎えます。真田勢は当初、家康の上杉征伐に加わるべく行動していましたが、西軍奉行からの家康弾劾の書状(下記補足6)を受け取り、昌幸・次男の信繁(幸村)は西軍に、信幸は東軍に味方(下記補足7)することにしたのです(犬伏の別れ)。これは、個々の立場に基づくものとも言えますが、昌幸がこれまで見てきた大名家の存亡から、真田家を残すための決断であったと思われます。

(補足6)
慶長五年(一六〇〇)七月十七日付 真田昌幸宛長束正家等連署状
 急度(きっと)申し入れ候。今度景勝発向の儀、内府公上巻の誓紙并びに大閤様御置目に背かれ、秀頼様見捨てられ出馬候間、各(おのおの)申し談じ、楯鉾(たてほこ)に及び候。内府公(家康)御違ひの条々別紙に相見え候。此の旨尤もと思し召し、大閤様御恩賞を相忘られず候はば、秀頼様へ御忠節有るべく候。恐々謹言。
   七月十七日 長大(長束大蔵大輔)正家(花押)
         増右(増田右衛門尉)長盛(花押)
         徳善(前田徳善院) 玄以(黒印)
     真田安房守殿 御宿所

(補足7)
慶長五年(一六〇〇)七月二十四日 真田信幸宛徳川家康書状(真田宝物館蔵)
今度安房守(あわのかみ)(昌幸)罷り帰られ候処、日比(ひごろ)の儀を相違(たが)へず、立たれ候事寄特千万に候。猶本多佐渡守(正信)申すべく候間、具(つぶさ)にする能はず候。恐々謹言。
   七月二十四日 家康(花押)
     真田伊豆守殿

石田三成らの西軍決起を知った家康以下東軍は、上杉征伐から引き返し、西に向かいました。その内、家康の跡継ぎ・秀忠率いる3万8千の徳川本体は、中山道を進みました(下記補足8)。その途上で、昌幸のこもる上田城を攻略することにしました。周辺で唯一西軍に組している有力大名だったからです。3千名程度といわれる上田勢は、今度は時間稼ぎの戦術に出ました。

(補足8)いよいよ真田安房守敵対申す由、中納言(秀忠)追々進発せしめ候。その方落ち度無き様、取り合ひの儀頼み入り候。もし大敵に及び候はば、この方へ注進これあるべく候。出馬、即時に踏みつぶし申すべく候(八月十三日仙石久秀宛徳川家康書状、「改撰仙石家譜」)

(慶長5年)
9月2日:秀忠、小諸城に到着(「但馬出石仙石家譜」)
9月3日:昌幸、信幸を通して秀忠に助命を嘆願(「佐竹家文書」)
9月4日:昌幸が降参しないので、秀忠が染屋台に本陣を進め、信幸の軍が、信繁が籠る砥石城に攻撃に向かう
9月5日:信繁が上田城に撤収、昌幸は降伏勧告に応じず
9月6日:徳川軍が稲の刈り取りをしようとしたところ、阻止する城兵と戦闘となり、大手門まで追うが、命令により撤収
     (「寛永諸家家系図伝」など徳川方史料)
9月8日:秀忠に、家康からの上洛命令が届く(下記補足9)
9月11日:秀忠、小諸城から出発(下記補足10)

(補足9)
わざわざ使者を以って申し入れ候、よって内府より急ぎ上洛せしむべき由申し越され候間、先ず先ず明日小諸まで罷り越し候。
その表万事油断なきの様、いよいよ仰せ付けられるべきの儀、肝要に存じ候。
なほ口上に申し含め候の条、詳にする能わず候。
恐々謹言。
         江戸中納言 秀忠御判
九月八日 羽柴右近殿 御陣所
(森家先代実録、信濃史料巻十八、長野県立歴史館アーカイブより)

(補足10)一書令啓上候、然者、黄門様(秀忠)十一日ニ小諸を御出、
九月廿三日 青常陸介 内修理亮 酒右京太夫
石田様
(堀文書、信濃史料巻十八、長野県立歴史館アーカイブより)

9月6日に戦闘がありましたが、小競り合いだったという説や、徳川方がまた大損害を受けたという説もあり、はっきりしません。
明確に言えるのは、
・秀忠軍は約10日間を費やしたが、上田城を攻略できなかった。
・総攻撃を行わず、家康の指示により関ヶ原に向かった。
・結果的に9月15日の関ヶ原の戦いに間に合わなかった。

昌幸は、秀忠軍の足止めに成功したのです。しかし、関ヶ原ではわずか一日の戦いで東軍が西軍に勝利し、まもなく上田城は接収されました。信幸などによる助命嘆願の結果、昌幸・信繁は、一命を取り留め、紀伊国九度山に配流となります。昌幸は、いつか罪を許されることを期待していましたが、11年後に亡くなりました。信繁がその後、大坂の陣で活躍することは余りにも有名です。上田は信幸の領地となりましたが、城は破却され、中心部は埋められました。信幸は、三の丸の屋敷で政務を執っていたのです。大坂の陣後の1622年(元和8年)には、松代へ加増転封になりました。

仙石忠政による上田城復興

廃城同然となっていた上田城を復興したのは、真田信之に代わって藩主となった、仙石忠政(生年:1578年〜没年:1628年)でした。彼はそれまで小諸藩主で、第二次上田合戦のときには父親の仙石久秀とともに参陣していました。久秀は、信長・秀吉に仕えた武将で、家紋は信長より拝領したものと言われています。忠政は久秀の三男でしたが、長男(久忠)は検校(盲目)、次男(久範)は関ヶ原で西軍に加わったため、跡継ぎとなりました。忠政は1622年(元和8年)に藩主となり、1626年(寛永3年)から幕府の許可を得て、上田城の復興に取りかかります。このときの将軍は家光でしたが、秀忠も大御所として健在でした。忠政を移したときに将軍だった秀忠は、修理料として銀子を与えたと言われています(補足11)。自らを含め二度も徳川軍を退けた上田城を、どのように見ていたのでしょうか。

(補足11)上田城は先年破却せしままなれば、修理の料として銀子二百貫目を賜うべし、心のままに修理すべき旨、懇の命(「改撰仙石家譜」?)

忠政は、家臣に復興工事に関する細かい指示書を出していて、復興への熱意を感じさせます。それによると、真田時代の城の姿の復元を目指していたことが伺えます(下記補足12)。埋められた堀を、掘り返していることから、少なくともレイアウトは真田時代を踏襲したと考えられます。現在、門や櫓のところに残る石垣は、そのときに築かれましたが、一部の古い形式の石垣は、真田時代のものか、その時代の石を転用した可能性があります。

(補足12)なわばりの時、古城の堀にゆがみがあるときには堀の両側を掘って直にせよ(「寛永三年仙石忠政築城覚書」、訳は「信濃上田城」による)

そして本丸には、天守七つの櫓と、二つの櫓門を建設しました(内部の御殿はなし)。二の丸などにも建物を建てる計画でしたが、工事開始から2年後に忠政が亡くなり中断されました。以後、基本的な城の構造は、忠政が復興したものが引き継がれました。復興後の姿が、信州上田城絵図(正保城絵図)として残されています。現在の残る城跡の基にもなっています。中断したとはいえ、わずか2年で城を復興した忠政にとって、上田城はどういう存在だったのでしょうか。

仙石氏は3代84年間、上田を統治しました。

藤井松平氏による統治とその後

1706年(宝永3年)但馬出石藩主の松平忠周(ただちか)が、仙石氏と交代で上田藩主になりました。この家系は藤井松平氏と呼ばれていて、家康以前からの松平一族でした(いわゆる「十八松平」の一つ)。忠周は当時、将軍徳川綱吉に側用人として仕えていました。幕府中枢にいたため、より江戸に近い領地に転封になったと見られています。彼は、徳川吉宗政権でも老中を務めました。藤井松平氏は基本的に、仙石氏が復興した上田城や藩の仕組みを維持しました。

しかし、この時代の上田城の敵は天災(洪水、地震、大火)でした。特に、忠周の子の忠愛(ただざね)の代には、1732年(享保17年)の千曲川洪水により、城の南の崖が大きく崩壊しました。その後4年をかけて、石垣の修築・造成が行われました。主にこの時に築かれた崖を覆う石垣は、現在目にすることができます。以降、経年劣化や大雨により破損した石垣の修理が幕末まで6回行われました(幕府への届出記録による)。

明治維新後、上田城は廃城となり、城の建物と土地は分割され、競売にかけられました。その結果、城地の多くは田畑となり、刑務所用地となった部分もありました。その状況を憂えた地元の有志たちは、城の中心部(本丸)に最後の城主だった松平氏を祀る松平神社を設立しました。その後、真田氏や仙石氏も合祀し、現在の真田神社になりました。また、二の丸を含むエリアは史跡に指定され、公園として活用されました。建物については、城に唯一残ったのは西櫓だけでした。地元の人たちはこれも憂えて、遊郭に売却されていた北櫓・南櫓を買い戻し、戦中戦後にかけて原位置に戻しました。更に真田の城として有名になると、両櫓をつなぐ櫓門も再建されました。現在上田市では、本丸にあった7つの櫓全てを元通りに再建することを目指して活動しています。

205.Matsuoyama Castle Part2

This article will describe how we visit the ruins of the encampments for the battle of Sekigahara (mainly of the Western Allies). We will finally go to the ruins of Matsuoyama Castle where Hideaki Kobayakawa was positioned.

Features

Introduction

This article will describe how we visit the ruins of the encampments for the battle of Sekigahara (mainly of the Western Allies). We will finally go to the ruins of Matsuoyama Castle where Hideaki Kobayakawa was positioned. In addition, as for the encampments of the Western Allies, we will visit them not only based on the defacto theory but also based on the new theories. Ogaki Castle may be a good starting point because the battle happened just after Mitsunari Ishida left the castle. You can see some exhibitions of him and the Sekigahara Battle in its restored main tower which has become a historical museum. Sekigahara Station is just few minutes from Ogaki Station.

The current Ogaki Castle
An example of its exhibitions inside
Sekigahara Station

Tour to Encampments of Western Allies based on Defacto Theory

It will be easy for visitors to visit the encampments based on the defacto theory because there are lots of information boards (also written in English). “Sekigahara Historical Landmark Tour” map, provided by the Sekigahara tourist association secretariat, will also help you. The following link is available in English.
(https://www.sekigahara1600.com/download/file/20200109155151.pdf)
So, let us first go to the encampment of Mitsunari Ishida on Sasaoyama Mountain, based on the defacto theory.

An example of the information boards

It may be better to go towards the Battle Site Memorial before reaching the mountain because you can find it easily. You can see the mountain where the flag of Mitsunari’s encampment stands.

The Battle Site Memorial, The flag on the right is Ieyasu’s family crest, while the flag on the left is Mitsunari’s family crest
Sasaoyama Mountain seen from the Battle Site Memorial, Notice the tiny white flags on the mountain

If you reach the foot of the mountain, you will eventually see that it was the encampment of Shima Sakon who was Mitsunari’s senior vassal. In fact, there is no evidence which proves that the mountain was certainly their encampments. The current historical sites were designated by the officials during the Meiji Era, probably based on the local traditions of the Edo Period. However, the top of the mountain looks suitable for the stronghold. You can see a panoramic view from the top, including Nangusan Mountain on the left, where Hiroie Kikkawa was positioned, and Matsuoyama Mountain on the right, where Hideaki was positioned. If Mitsunari would have been on the top, he would have been able to see any suspicious actions by the lord.

The encampment of Shima Sakon
The entrance to Mitsnari’s encampment
The stone monument of Mitsnari’s encampment
The view from the mountain, The mountain on left is Nangusan and the mountain on the right is Matsouyama

Our next target will be the grave site of Yoshitsugu Otani, after passing the encampments of other lords of the Western Allies, such as Yoshihiro Shimazu, Yukinaga Konishi, and Hideie Ukita. You need to walk for few kilometers to reach the target. However, some soldiers who joined the battle testified that the lords were positioned together in the range of only few hundreds of meters. This is another mystery that his often debated by historians and experts.

The encampment of Yoshihiro Shimazu
The encampment of Yukinaga Konishi
The encampment of Hideie Ukita

You will eventually enter the Yamanaka area (which directly means “mountain area”), not like the Sekigahara field. There are actually some ruins of encampments, made by soil, which Yoshitsugu might have built. His grave is in the area, which is said that his retainer originally buried his head there. Takatora Todo, who had been his enemy, heard about it and developed the grave as we can see now. There are always offerings (such as flowers) in front of the grave, from his fans. This is probably because of his episodes in the battle. Yoshitsugu joined the Western Allies because of his friendship with Mitsunari but was defeated by the betrayal of Hideaki (according to the defacto theory).

The grave site of Yoshitsugu Otani

Tour to the Encampments of the Western Allies based on New Theories

Let us next go to the encampment of Yoshitsugu Otani from his grave nearby.
His encampment has been designated based on the defacto theory while a new theory says it was, in fact, that of the Shimazu troops. By the way, there is the view spot of Matsuoyama Mountain near the encampment as well. You can see the flag of Hideaki’s encampment from that spot. I think the view is one of the reasons why Yoshitsugu’s encampment was designated nearby in the defacto theory. The theory says Yoshitsugu was positioned in order to better monitor the betrayal of Hideaki. On the other hand, in the new theory, Yoshitsugu was actually in the Sekigahara field, so another lord was expected to use the encampment instead of him.

The encampment of Yoshitsugu Otani
The view spot of Matsuoyama Mountain
The flag of the encampment of Hideaki Kobayakawa on Matsuoyama Mountain, seen from the view spot

We will next go to the encampment of Mitsunari Ishida, based on the new theory, after climbing down the mountain area. If you walk on the Old Nakasendo Road, you will eventually see a hill up ahead, which is the encampment, called “Jigai-ga-oka”. The hill is also a historical site of Jinshin War during the Ancient Time, called “Jigai-mine-no-sanbon-sugi” which means “The three cedars on Suicide Hill”. A tradition says as followed:
Prince Otomo was defeated by Prince Oama during the war and killed himself in another place. People around the hill, who loved him, got his head and buried in the hill. The three cedars are said to be the mark, which you can visit and see.

Jigai-ga-oka Hill
The three cedars on Suicide Hill, The two remaining cedar trees are not accessible however, because they have a chain fence around them

There is one more spot regarding both the Sekigahara Battle and the Jinshin War, after going on the road over Fujikogawa River. You can find Fuwanoseki Museum, which are the ruins of Fuwanoseki (which means Fuwa Gateway). The new theory says this spot was the encampment of Yoshitsugu Otani. In the Jinshin War, the gateway was the border between the forces of Otomo (the west) and Oama (the east). In the Sekigahara Battle, Sekigahara (which directly means “gateway field”) was that of the Western and Eastern Allies.

Fujikogawa River in the front and Fuwanoseki Museum on the hill in the back
The Fuwanoseki Museum as the ruins of Fuwa Gateway, which might have also been the encampment of Yoshitsugu Otani, The white flag says “Fuwa Gate” while the red flag says “Jinshin War”

We will get closer to Matsuoyama Mountain. There are lots of flags of the Kobayakawa Clan at its entrance. It has a nice atmosphere.

The entrance to Matsuoyama Mountain as the encampment of Hideaki Kobayakawa, The yellow flags show the family crest of Kobayakawa. The 4 flags on the left show two sickles crossing each other.

Going to Matsuoyama Mountain

Matsuoyama Mountain is 293m above sea level and about 200m above the foot of the mountain. If you drive your car, you can park it at the foot. The trail to the top is part of Tokai Natural Trail, which has been well developed. The number of Hideaki’s troops were said to be about 8,000 to 15,000. They were probably stationed from the foot all the way to the top. If the Toi-deppo story is true, the soldiers at the foot would have been able to hear it.

The starting point of the trail, Notice the basket of sticks which is free for visitors to use.  Make sure you return it to the original basket after using it
The trail at the foot

Matsuoyama Castle is often called the encampment of Hideaki Kobayakawa, in fact, it was a full-scale castle. It had the main enclosure on the top and several other enclosures on its ridges. They were surrounded by earthen walls one by one and were divided by dry moats from each other. It also had ditches on the ridges and vertical moats on the slopes in order to prevent enemies from invading it. The castle was mostly fortified by the Western Allies just before the Sekigahara Battle. It was done using natural terrain and construction with soil.

The diorama of Matsuoyama Castle, exhibited by Sekigahara Town History
& Folklore Museum

The trail looks like a well-developed forest road before turning into a fork. There is a sign which says 850m to the top. As you get close to the top, the trail goes beside a ridge which was the eastern enclosure of the castle. If you were an enemy back then, you would have been attacked by the defenders above.

Turn right, at the flag, Notice the drain on the road.  When it rains, the water flows down the mountain, and goes to the drains
850m to the top
The trail goes beside the eastern enclosure

You will eventually see several flags standing on the main enclosure of the top above. One of them is that of Hideaki Kobayakawa’s encampment, which you saw from the view spot of Matsuoyama Mountain. The view from the top is so nice that you will be encouraged to stop and stare for a while. It would have been the view of Kobayakawa according to the defacto theory.

The top will be soon
The main enclosure on the top
The flag of the encampment of Hideaki Kobayakawa
The view of the Sekigahara field from the top of Matsuoyama Mountain, It would have been great if the town decided to cut the trees so that viewers could get a better view of Sekigahara Field

Is it a Castle or is it an Encampment?

Let us check out if Matsuoyama Castle is worth for a full-scale castle at the site. In fact, the opposite side of the trail we climbed looks more fortified, according to the pamphlet of Matsuoyama Castle. (unfortunately, the pamphlet is only available in Japanese)
We will enter the castle from the side.

The layout of the castle (from the pamphlet of Matsuoyama Castle), we first came from above

The path of the entrance gets narrower by being cut by the ditches on both sides. You will next pass an enclosure like a position, which is called the enclosure like Umadashi (the position which sticks out from the gate).

The narrow entrance
The enclosure like Umadashi

The path gets narrower again and wind towards the main enclosure. The entrance of the main enclosure is a square, surrounded by earthen walls, which is generally called Masugata. The route you walked on right now may be the front of the castle, where Hideaki might have also been at.

The path becomes narrow again
The path goes close to the main enclosure, Notice the wooden steps that were added later on by the town
The Masugata system at the entrance of the enclosure

You can also walk down to the dry moats surrounding the main enclosure, from the front of the Masugata system. You will see the vertical cliffs on the slopes of the enclosure, which were artificially cut for defense, on the way to the moats. The bottom of the moats looks spacious tough it is covered with trees and grass now. Historians speculate that it was used as passages or stations for soldiers. The moats also have earthen walls like normal enclosures have.

Going down to the dry moats
The vertical cliffs, Notice the narrow road partially covered in plants.  On the right, is the artificially cut soil, in order ot make the slope steeper for the enemies
The bottom of the moat
The earthen walls on the moat, Notice the sign in Japanese saying “altered earthen walls”

Finally, we will climb another enclosure on a hill, the opposite of the main enclosure. The top of the enclosure is leveled, probably in order to accommodate soldiers in the past. Overall, Matsuoyama Castle must have been a large basement for the Sekigahara Battle. I have confirmed that it was not only a simple encampment but also a full-scale castle.

Climbing the slope to another enclosure
The top of the enclosure

My Impression

After visiting the Sekigahara area, I think it still has a mysterious vibe and can accept adventurous spirits with many theories. In addition, I also learned that the area has a long history including the gateway and battle between eastern and western Japan since the ancient time. In fact, the battle between them still continues today in the category of noodles. You can buy two types of instant noodles for eastern and western Japan there at the souvenir shop. Gifu Sekigahara Battlefield Memorial Museum is a very popular spot for visitors where you can learn about the battle and buy other souvenirs. You can also get Goshuin stamps (you can stamp a piece of paper to commemorate your experience) of the encampments you visited there; However, you will need to show the pictures to the counter staff as evidence.

The Gifu Sekigahara Battlefield Memorial Museum
The two types of instant noodles for eastern and western Japan, The left is the “western type” while the one on the right is the “eastern type”.
The Goshuin stamps for three encampments, The left is the grave of Otani, the center represents Matsuoyama Mountain, and finally the one the right is Sasaoyama

That’s all. Thank you.

Back to “Matsuoyama Castle Part1”

205.Matsuoyama Castle Part1

The battle of Sekigahara, which occurred in 1600, is one of the biggest events in Japanese history. The highlight of the battle has been said to be the betrayal of Hideaki Kobayakawa. However, historians are trying to re-create the Sekigahara story by reviewing the few remaining primary sources and some of the secondary ones which were reliable.

Location and History

Introduction

The battle of Sekigahara, which occurred on the 15th of September 1600 (according to the lunar calendar), is one of the biggest events in Japanese history. The highlight of the battle has been said to be the betrayal of Hideaki Kobayakawa. The widely accepted theory says the followings. Hideaki first supported the western allies and settled on Matsuoyama Castle, in the south of the Sekigahara field. However, he still waited to see the battle for a while, wondering which ally would be better, the eastern or the western. He had made a secret agreement with Ieyasu Tokugawa, who was the top of the eastern allies, to support. Initially, Koyakawa did not move, therefore Ieyasu got tired of waiting. He then ordered his soldiers to shoot at the Hideaki’s troops. The shooting was called “Toi-deppo” which means to force by guns. Hideaki was very surprised to hear that. In that instance, he quickly decided to support the eastern allies. This indecision by Kobayakawa lead to the death of Mitsunari, but gave victory to Ieyasu.

The folding screens of the Sekigahara Battle, owned by Sekigahara Town History and Folklore Museum (licensed under Public Domain via Wikimedia Commons)

Recent studies suggest the betrayal of Hideaki and the Toi-deppo story.
The whole story of the Sekigahara battle is consisted of very few primary sources and many other secondary sources. The Toi-deppo story comes from one of the secondary sources. The Sekigahara Battle is long. One part of the story refers to Toi-Deppo, which was first written in the Keicho Gunki, a war chronicle which was written over 50 years after the battle. If the story is a fiction, the timing of Hideaki’s decision would also be doubtful. Historians are trying to re-create the Sekigahara story by reviewing the few remaining primary sources and some of the secondary ones which were reliable. In addition, Matsuoyama Castle has been said to be the base of Hideaki Kobayakawa during the Sekigahara battle. However, it would also be important to know when and how the castle was built and used.

The portrait of Hideaki Kobayakawa, owned by Kodaiji Temple (licensed under Public Domain via Wikimedia Commons)

This article will explain three different theories of Hideaki and Matsuoyama Castle with three different viewpoints.
The viewpoints will include:
a. What and where did Hideaki go before the Sekigahara battle?
b. Why did Sekigahara become the battlefield and when and how did Hideaki settle on Matsuoyama Castle?
c. When did Hideaki really decided to support the eastern allies?

The theories on this article will include:

  1. The defacto theory including the Toi-deppo story
  2. The theory that Hideaki was not a betrayer
  3. The theory that the western allies would attack Matsuoyama Castle

    As a preface, I will describe the prehistory of Hideaki and Matsuoyama Castle before the battle.

Hideaki and Matsuoyama Castle before Sekigahara Battle.

Hideaki was born in 1582 as the fifth boy of Iesada Kinoshita who was the big brother of Kitano-mandokoro, the first lady of Hideyoshi Toyotomi. He was adopted by Hideyoshi when he was a child and was raised by Kitano-mandokoro. Surprisingly, Hiedaki celebrated his Coming of Age at only 7 years old and became a noble. This was because he was one of the candidates to be Hideyoshi’s successor. However, after Hideyori Toyotomi, Hideyoshi’s own child was born, Hideaki was adopted again by the Kobayakawa Clan. Hideyoshi thought Hideyori would have become his successor.

The portrait of Iesada Kinoshita, the biological father of Hideaki, owned by Kenninji Temple (licensed under Public Domain via Wikimedia Commons)

There is an interesting episode about that from a war chronicle as follow. Hideyoshi originally wanted to adopt Hideaki to the Mori Clan and for the Mori Clan to take over, which was the head family of the Kobayakawa Clan. Takakage Kobayakawa, the lord of the clan offered to Hideyoshi to accept Hideaki to protect his master. However, according to historians, Takakage probably decided it by himself. This was because Takakage was an independent lord after he was given his own territory by Hideyoshi. Takakage assumed he would return the territory to Hideyoshi so that he could build a good relationship with him.

The portrait of Takakage Kobayakawa, owned by Beisanji Temple (licensed under Public Domain via Wikimedia Commons)

Hideaki’s new territory was at Chikuzen Province (which is part of Fukuoka Prefecture now) which was one of the basements for the invasion of Korea by Hideyoshi. Hideaki also went to Korea as the supreme commander when he was 16 years old (so, it was just a formality). However, when he went back to Japan in 1598, he was forced to move to Echizen Province (the current Fukui Pref.) by Hideyoshi. The reason for it is uncertain. War cornicles suggest that Hideaki made a mistake in the invasion, while historians speculate that Hideyoshi wanted to rule Chikuzen Province directly to boost his invasion. The fact is, after Hideyoshi died, that Hideaki returned to Chikuzen Province and was considered one of the great lords of Japan, following the members of Counsil of Five Elders in the top government. This would trigger the Battle of Sekigahara.

The Portrait of Hideyoshi Toyotomi, attributed to Mitsunobu Kano, owned by Kodaiji Temple (licensed under Public Domain via Wikimedia Commons)

Matsuoyama Castle was located on the border between Omi (the current Shiga Pref.) and Mino (Gifu Pref.) Provinces. A record says that a retainer of Nagamasa Azai, who owned Omi Province, was assigned to the castle during the Sengoku Period. This was probably because Nagamasa was against Nobunaga Oda who owned Mino Province at that time. Nobunaga would eventually get Omi Province before the castle was abandoned. On the 10th of Argust, 1600 (according to the luna calendar), Mitsunari Ishida entered Ogaki Castle. Mitsunari ordered his retainer to resume Matsuoyama Castle. Mitsunari thought that his Western Allies would attack the Eastern Allies based on Ogaki Castle, backed up by other mountain castles. Matsuoyama Castle was one of them. A historian speculates that Mitsunari thought that Terumoto Mori, the greatest lord in the Western Allies would enter Matsuoyama Castle. Anyway, the castle was refortified again to prepare for the battle.

The flag of Hideaki Kobayakawa at the ruins of Matsuoyama Castle; You can see this flag on top of the mountain, This is a modern flag that helps tourist find this location

Defacto theory including Toi-deppo story

It is confirmed that the Western Allies captured Fushimi Castle on the 1st of August (according to the lunar calendar). It is also certain that the troops of Hideaki Kobayakawa joined the attackers as the main force. After that, according to the de facto theory, many of the Western Allies, including Mitsunari Ishida, stayed in Ogaki Castle, while Hideaki marched over to Omi Province (the current Shiga Province). There is evidence of his actions there. remains at a temple of the province. There is a noticeboard where Hideak’s soldiers were asked not to be violent in the temple. Hideaki still supported the Western Allies, however, he also negotiated with the Eastern Allies. A secret letter from Nagamasa Kuroda and Yoshinaga Asano was given to Hideaki before the battle. The letter is written as followed.

“We (Nagamasa and Yoshinaga) will need to serve Kitano-mandokoro.
You need to decide whether or not you will support us until Ieyasu arrives here.”

Kitano-mandokoro took care of Nagamasa earlier on. He managed to persuade Hideaki that it would be needed to support the Eastern Allies if Hideaki wanted to serve Kitano-mandokoro from then on.

The temple whom Hideaki gave the noticeboard (quoted from the website of Maibara City)

Ieyasu arrived at Aakasaka Camp on the 14th of September, near Ogaki Castle. He wanted to have an open field battle, which he was good at, so he needed to lure Mitsunari out from the castle. Ieyasu intentionally announced that he would attack Sawayama Castle, which was Mitsunari’s home and far to the west from Ogaki. When Mitsunari heard this, he was surprised and left the castle in a hurry, got ahead of Ieyasu, and took up positions on Sekigahara Field on the way to Sawayama. Hideaki also reached Matsuoyama Castle in the south of Sekigahara in accordance with Mitsunari’s instructions. Historians speculate that Mitsunari might have tried to escape to Sawayama Castle with his own decision. This is because a letter of Hiroie Kikkawa, who was one of the members of the Western Allies on Nangusan Castle between Ogaki and Sekigahara, says so. However, Mitsunari couldn’t do that because had to prevent the eastern allies from invading Sekigahara on the way there. Yoshitsugu Otani, a lord of the Western Allies only expected that Hideaki would betray him, therefore, Yoshitsugu’s troops moved closer to Matsuoyama.

The portrait of Mitsunari Ishida, from the database of Historiographical Institute, the University of Tokyo (licensed under Public Domain via Wikimedia Commons)

The battle between the Eastern and the Western Allies occurred early in the morning on the 15th of September. It went back and forth until noon. Hiroie’s troops on Nangusan and Kobayakawa’s troops didn’t move because of their secret pact with Ieyasu. However, Ieyasu got annoyed as Hideaki had also promised that he would join the Eastern Allies. That’s why Ieyasu ordered the Toi-deppo (a way to induce or encourage solider to move by shooting directly at them). Hideaki’s decision happened around noon. Some of the soldiers who joined the Western Allies testified after the battle as followed:

“The Eastern Allies and Otani’s troops battled each other 6 or 7 times in the morning. Kobayakawa’s troops, then, rushed down from the mountain into Otani’s side and destroyed them.”

As for the Toi-deppo story, it may be a fiction as mentioned above. However, a historian found another tradition that might have been the origin of the story as followed:

An old man in Bizen Province (the current Okayama Pref.) heard about an interesting story from Kobayakawa’s retainer. During the battle, Hideaki heard gunshots at the foot of the mountain. His retainers reported that the shooters of the Eastern Allies said that the gunshots were not intentional and that they just misfired. The retainers also added it might have included something else.

The historian speculates that the shooting could have been an indirect warning from Ieyasu. However, this theory is still not the number one theory according to historians.

The Portrait of Ieyasu Tokugawa, attributed to Tanyu Kano, owned by Osaka Castle Museum (licensed under Public Domain via Wikimedia Commons)

Theory that Hideaki was not a Betrayer

I will next explain a new theory about Hideaki and Matsuoyama Castle. Accorting to this theory, it is uncertain where Hideaki was after the battle of Fushimi Castle just before the Sekigahara Battle. The de facto theory says he was in Omi Province at that time. However, that comes from the family records of the Inaba Clan which was written during the Edo Period. The records also say their founder, who was a senior vassal of Hideaki, captured Matsuoyama Castle for the Eastern Allies. That means the records were manipulated by his descendants to show their contributions to the current shogunate, which may not be plausible now. On the other hand, a lord of the Eastern Allies reported that Hideaki stayed in Ogaki Castle just before the Sekigahara Battle. This is contradictory. Overall, in my opinion, I think Hideaki was undecided as to who he would support until the moment he rode up the mountain.

The portrait of Masanari Inaba, who was a senior vassal of Hideaki, owned by Kanagawa Prefectural Museum of Cultural History (licensed under Public Domain via Wikimedia Commons)

In fact, there is also no certain evidence where Hideaki was positioned at the beginning of Sekigahara Battle. However, another evidence suggests it. The letter of Hiroie Kikkawa, mentioned above, says an interesting matter just before the battle.

“The Western Allies moved from Ogaki Castle to Yamanaka (the west of Sekigahara) in order to rescue Yoshitsugu Otani because Hedeaki would be fighting against them.”

According to the letter, Hideaki and Yoshitsugu had already arrived early to inspect the field. In addition, a letter that Masamune Date wrote, who was reported from his relative about the Sekigahara battle, also says:

“The Western Allies moved from Ogaki Castle to support Nangusan Castle.”

Overall, historians speculate why Sekigahara became the battlefield as followed: Ieyasu at Akasaka Camp first tried to attack Nangusan Castle. Mitsunari heard about this and tried to intercept Hideaki, so he decided to leave Ogaki Castle and went to Sekigahara. Then, Hiroie Kikkawa at Nangusan Castle surrendered to Ieyasu who next ordered his troops to chase after Mitsunari. The Western Allies eventually reached Yamanaka and positioned themselves, which was not Sekigahara. This is another different point from the defacto theory.

The portrait of Hiroie Kikkawa, owned by Historiographical Institute the University of Tokyo (licensed under Public Domain via Wikimedia Commons)

If they are true, Hideaki declared he would join the Eastern Allies at the latest the day before the battle. The battle started around 10am, where Hideaki joined it at the same time, and the Western Allies were defeated by the Eastern Allies quickly. They are different from the defacto story. The theories of the starting time of the battle are also different depending on the testimonies of the participants. Historians speculate as followed. In the early morning at Sekigahara field which was covered in fog. The Otani troops went ahead from the Yamanaka area to the Sekigahara field. It first battled against the frontline of the Eastern Allies. When the fog cleared up around 10am, the Kobayakawa troops attacked the Otani troops which would eventually be destroyed. After that, the main forces from both the Eastern and Western Allies fought against each other at the Yamanaka area, but the Western Allies were also destroyed in a short amount of time. Ieyasu wrote in his letters that Hideaki worked well in Sekigahara and his troops destroyed the Western Allies including Mitsunari in Yamanaka.

The last position of Ieyasu Tokugawa at the Sekigahara field, this is the encampment of the eastern allies, The two inner flags show Ieyasu’s family crest, while the two outer flags show his motto

The theory that Western Allies would attack Matsuoyama Castle

The previous theory can help us understand that Hideaki was not a betrayer in the middle of the battle. However, the theory is consisted of much circumstantial evidence. It doesn’t show us the clear conflicted formation between Hideaki and the Western Allies. (Situations of battles may sometimes be like that.) Another theory by another historian may clear this up. The main idea of the theory is that the Sekigahara Battle happened when the Western Allies tried to destroy Hideaki’s troops on Matsuoyama Castle. In this theory, Hideaki was stationed in Omi Province and negotiated with the Eastern Allies before entering the castile, the same as the defacto theory. However, the theory speculates that Hideaki made his decision to join the Eastern Allies in advance of reaching Matsuoyama Castle, which is the different point from the defacto theory.

The ruins of Matsuoyama Castle

The biggest difference in this theory from other ones is the reason why Mitsunari left Ogaki Castle. According to this theory, Mitsunari heard about Hideaki’s rebellion during the meeting at the castle on the 14th of September, the day before the Sekigahara Battle. Mitsunari decided to leave the castle to destroy Hideaki. One of the pieces of evidence for the theory is the same part of the letter Hiroie Kikkawa wrote, as the previous theory uses. It says “the Western Allies went from Ogaki Castle to Yamanaka (near Sekigahara) in order to rescue Yoshitsugu Otani because Hideaki would be fighting against them” in the previous theory. However, the same part says in this theory that “The Western Allies were going to attack Yamanaka, which meant Hideaki’s rebellion became obvious, so Yoshitsugu Otani followed them from Ogaki Castle.” Why are the interpretations of the same part so different between each other? This is probably because letters of warlords were usually written using simple and often vague facts, so that the interpretations of the current historians may sometimes become different. Another reason is sometimes the messenger would be intercepted, and vague instructions would be hard for the enemy to understand.

The grave of Yoshitsugu Otani in the Yamanaka area

Mitsunari was positioned on Jigai-ga-oka Hill in front of Matsuoyama Castle on Matsuoyama Mountain, not on Sasaoyama Mountain which the defacto theory says. According to the testimonies of some soldiers who joined the battle, the Ukita and Konishi’s troops were on the frontline against the castle to the south, back upped by the Shimazu’s troops. Mitsunari’s troops were in the eastern side of the Shimazu. The Eastern Allies including Ieyasu chased after Mitsunari in order to rescue Hideaki who had already joined them. That’s why they saw, from the east, the Western Allies like Miatunari on the frontline, back upped by the Shimazu’s troops, which were written in other records. The Otani’s troops finally arrived and was positioned at Sekigahara field in the eastern side of his allies. As a result, they were first attacked by the Eastern Allies, then sandwiched between the Eastern Allies and Hideaki’s troops, and eventually destroyed.

Jigai-ga-oka Hill

Some of the soldiers who joined the Western Allies testified after the battle as followed:

“The Eastern Allies and Otani’s troops battled each other 6 or 7 times in the morning. Kobayakawa’s troops, then, rushed down from the mountain into Otani’s side and destroyed them.”

This is the same testimony that proves the defacto theory.
It is very interesting that this testimony proves two different situations.

To be continued in “Matsuoyama Castle Part2”