{{Short description|Battle in the Genpei War}} {{Infobox military conflict | conflict = Battle of Hashidayama | place = "Hashida Mountain", Suruga Province | result = Minamoto clan victory | partof = Genpei War | date = August 25, 1180 Jishō calendar | combatants_header = Belligerents | combatant1 = Sasa Rindo|20px Minamoto clan | combatant2 = Ageha-cho|20px Taira clan | campaignbox = {{Campaignbox Genpei War}} | commander2 = {{plainlist | * {{flagicon|Taira clan|size=20px}} {{Interlanguage link multi|Kagehisa Matano|jp|3=俣野景久|v=ib}} * {{flagicon|Taira clan|size=20px}} {{Interlanguage link multi|Tachibana no Tomochi|jp|3=橘遠茂|v=ib}} }} | commander1 = {{plainlist | * Sasa Rindo|20px Yasuda Yoshisada * Kudo Kagemitsu }} | width = 375px | image = Lake Sai march evening 5-30pm from eastern end|375px | caption = Image of Lake Saiko, around the area the battle is believed to have happened. }}

'''The Battle of Hashidayama''' (波志田山合戦) was one of the battles during the Genpei War, taking place in 1180. The location of Mount Hashida is assumed to be at the northern foot of Fuji,<ref>{{Cite book |url=http://www5a.biglobe.ne.jp/~micro-8/toshio/azuma/118008.html |title=Azuma Kagami |page=８月２５日 |chapter=１１８０年（治承四年) |trans-chapter=1180 (4th year of Jisei) |quote="而るに昨日昏黒に及ぶの間、富士の北麓に宿すの処、景久並び / He was then in the northern foothills of Mount Fuji, where he lodged yesterday in the dark"}}</ref> but the exact location is unknown due to various theories. This battle is what brought awareness to {{Interlanguage link multi|The Kai Minamoto clan|jp|3=甲斐源氏}} in Japan.

== Overview == According to Azuma Kagami,<ref>In the English page for the Genpei War, after the sixth footnote, a mention to this battle is said (and i quote): "However he (Minamoto no Yoritomo) successfully made it to the provinces of Kai and Kōzuke, where the Takeda and other friendly families helped repel the Taira army."</ref> Prince Mochihito, son of Emperor Go-Shirakawa, issued a decree to the Minamoto clan in the east to defeat the Taira clan, which was sent to Minamoto no Yoritomo in Izu, Kai and Shinano provinces. Minamoto no Yoritomo raised an army in August of the same year, leading warriors from Izu and Sagami provinces, and was defeated on August 23rd at the Battle of Ishibashiyama by an army led by Ōba Kagechika of the Taira clan. <ref>{{Cite book |title=Azuma Kagami |date=1260s |page=８月２５日 |chapter=１１８０年（治承四年) |trans-chapter=1180 (4th year of Jisei) |quote="五郎景久、駿河の国の目代橘の遠茂が軍勢を相具し、武田・一條等の源氏を襲わんが"/"Goro Kagehisa of Matano and Tachibana no Toumochi of Suruga, with an army, went to the province of Kai to attack the Minamoto clans of Takeda, Ichijo, and others"}}</ref>

Some clans were related to the Izu warriors close to Minamoto no Yoritomo, such as {{Interlanguage link multi|The Kai Minamoto|jp|3=甲斐源氏}} (Ruled by the Takeda clan), founded by Minamoto no Yoshikiyo and his son {{Interlanguage link multi|Minamoto no Kiyomitsu|lt=Kiyomitsu|jp|3=源清光}} in around 1131,<ref>{{Cite web |title=Yamanshi Prefecture |url=https://www.pref.yamanashi.jp/miryoku/rekishi/history/index.html |website=pref.yamanashi.jp |language=ja |quote=1131年ころ、甲斐国には源義清、清光の親子が入り、甲斐源氏を興します |trans-quote=Around 1131, father and son Yoshikiyo and Kiyomitsu Minamoto entered Kai Province and established the Kai Minamoto clan.}}</ref> who controlled the {{Interlanguage link multi|Kofu Basin area|jp|3=甲府盆地}}. Others, such as the Akiyama clan of {{Interlanguage link multi|Kagami Tohmitsu|jp|3=加賀美遠光}} in Kai, and the Ogasawara clan in Shinano, served the Taira clan and/or had a residence in Kyoto.

Among the clans related to the Izu warriors, Kudo Kagemitsu agreed with Yoritomo's military expedition, and his family members, Shigemitsu and Chikamitsu, went to Yoritomo's side.<ref name=":1">{{Cite book |title=Azuma Kagami |page=８月２５日 |chapter=１１８０年（治承四年、庚子） |trans-chapter=1180 (4th year of Jisei) |quote="安田の三郎義定・工藤庄司景光、石橋に於いて合/Yoshisada Yasuda's Saburo Yoshisada and Kudo Shoji Kagemitsu,, heard of the battle at Ishibashi and met Kagehisa and others at Mount Hashita"}}</ref> Yoritomo hid in the Hakone Mountains after the defeat at Mt. Ishibashi, planning to dispatch Hōjō Tokimasa and Yoshitoki, father and son, to Kai province (according to Azuma Kagami),<ref name=":0">According to "The Tale of the Heike", the Hojo father and son fled to Kai Province on their own initiative, regardless of Yoritomo's intentions.</ref> and it is believed that Yoritomo was aware of the existence of the Kai Minamoto.

According to Azuma Kagami, when the defeat at the Battle of Ishibashiyama was reported to Kai, the Kai Minamoto clan, led by Yasuda Yoshisada and Kudo Kagemitsu went to rescue Minamoto no Yoritomo (as well as other clans close to him).<ref name=":1" />

On the Taira side, Kagehisa Matano, the younger brother of Kagechika Oba, dispatched an army to Kai together with Tachibana no Tomochi, the leader of the Suruga province, and the two armies clashed on August 25 at "Mount Hashida". The location of "Mount Hashida" is thought to be around Fujikawaguchiko Town/Mt. Ashiwada, located between Saiko Lake and Lake Kawaguchi at the northern foot of Fuji.<ref>{{Cite web |title=深読み吾妻鏡/波志太山合戦の顛末 |url=https://history.orange-shoes.biz/深読み吾妻鏡/波志太山合戦の顛末/}}</ref>

== Battle == According to Azuma Kagami, 100 bowstrings of the Taira's army were broken by rats during a stay in a village.<ref>{{Cite book |title=Azuma Kagami |quote="に郎従帯する所の百余張の弓弦、鼠の為喰い切られをはんぬ/Kagehisa and his followers, more than a hundred bows and strings were eaten away by rats"}}</ref> Soon after in the morning, he heard that Yasuda no Yoshisada, Kudo Kagemitsu, and his sons had become ready to fight a battle, and while the pro-Minamoto forces were setting out from Kai Province, they met Kagehisa and others at Hashidayama. The battle began with a strong attack by Yasuda's forces, consisting mostly of arrow barrages. Although the Taira forces did fight back, Kagehisa and his men had their bowstrings cut, and had to take up swords. Many of the Taira forces were killed. Yasuda's subordinates and others were also forced to take up swords at a point. However Kagehisa managed to flee.<ref>{{Cite book |url=http://www5a.biglobe.ne.jp/~micro-8/toshio/azuma/118008.html |title=Azuma Kagami |page=８月２５日 |chapter=１１８０年（治承四年、庚子） |trans-chapter=1180 (4th year of Jisei) |quote="然れども景久雌伏せしめ逐電すと/However, Kagehisa was forced to lie low and fled"}}</ref> The Taira eventually left and were routed.<ref>{{Cite book |title=Azuma Kagami |page=８月２５日 |chapter=１１８０年（治承四年、庚子） |trans-chapter=1180 (4th year of Jisei) |quote="依って、太刀を取ると雖も、矢石を禦ぐこと能わず/Therefore, even though they took up swords, they could not defend themselves against the arrow stones."}}</ref>

In the {{Interlanguage link|Sankai-ki|jp|山槐記}}, Minamoto no/Nitta Yoshishige, the leader and founder of the Nitta clan, sent a letter to {{Interlanguage link|Fujiwara no Tadamasa|jp|藤原忠雅}} (Tadamasa was the elder brother of Nakayama Tadachika, the author of the "Sankaiki"), a feudal lord close to the Taira clan, reporting Takeda Nobuyoshi, one of the leaders of the Kai Minamoto clan, as an anti-Taira force alongside Yoritomo. The victory at Mount Hashida is thought to have triggered awareness of the existence of the Kai Minamoto clan in the eastern part of Japan and elsewhere.<ref>秋山敬「源頼朝の挙兵と甲斐源氏」『山梨県史』</ref>

== Aftermath == On August 28, Yoritomo escaped from Kanagawa Prefecture to Awa Province (Chiba) to rejoin his army and rallied many warriors in the East. The rest of the Minamoto and Takeda Nobuyoshi had received word of the Battle of Mount Hashida in early-mid September <ref>{{Cite book |url=http://www5a.biglobe.ne.jp/~micro-8/toshio/azuma/118009.html |title=Azuma Kagami |page=９月１０日 |chapter=１１８０年（治承四年、庚子） |trans-chapter=1180 (4th year of Jisei) |quote="甲斐の国の源氏武田の太郎信義・一條の次郎忠頼以下、石橋合戦の事を聞き、武衛を 尋ね奉り、駿河の国に参向せんと欲す/Nobuyoshi of Takeda, Jiro Tadayori of Ichijo and others of the Minamoto clan in the Land of Kai heard of the Battle of Mount Hashida and asked for the military assistance to go to Suruga Province.}}</ref> and were asked to go to Suruga province to fight, however, Takeda Nobuyoshi, Ichijō Tadayori and others of the Kai Minamoto clan went to {{Interlanguage link|Ina County|jp|伊那郡}}, Shinano Province (modern day Nagano Prefacture) and defeated Taira Tomonori in modern day Komagane first.<ref>{{Cite book |url=http://www5a.biglobe.ne.jp/~micro-8/toshio/azuma/118009.html |title=Azuma Kagami |page=９月１０日 |chapter=１１８０年（治承四年、庚子） |trans-chapter=1180 (4th year of Jisei) |quote="而るに平氏の方人等信濃の国に在りと。仍って先ず彼の国に発向す/The Taira clan's men and others were in Shinano. Therefore I shall first set out for his country."}}</ref> On November 9th, the Kai Minamoto clan, headed by Takeda Nobuyoshi, went to Suruga to fight the Taira force at the Battle of Fujigawa, which they won.

==References== {{reflist}}

==Sources== [http://www5a.biglobe.ne.jp/~micro-8/toshio/azuma.html Azuma Kagami] (in Japanese) <br>English translation of [https://web.archive.org/web/20100807003350/http://libweb.uoregon.edu/ec/e-asia/read/heike-whole.pdf ''The Tale of the Heike''] (archived)<br>https://history.orange-shoes.biz/深読み吾妻鏡/波志太山合戦の顛末/ (Secondary)<br>https://ameblo.jp/oyomaru-0826/entry-12415959663.html (Secondary)

{{coord missing|Shizuoka Prefecture}}

{{DEFAULTSORT:Hashidayama 1180}} Category:Battles of the Genpei War Category:Mount Fuji Category:Conflicts in 1180 Category:1180s in Japan Category:1180 in Asia Category:Military history of Yamanashi Prefecture Category:Mountain warfare in Asia