# Battle of Okitanawate
The Battle of Okitanawate (沖田畷の戦い) was fought in 1584, on the 24th day of the 3rd month of Tenshō ([Japanese era name](https://www.edgepedia.org/japanese-era-name) used for dating) 12, in the wetlands of Hizen Province near Shimabara (in present-day Nagasaki Prefecture), between the Ryūzōji army under [Ryūzōji Takanobu](https://www.edgepedia.org/ryuzoji-takanobu) and a coalition of the Shimazu and Arima clans under Shimazu Iehisa and [Arima Harunobu](https://www.edgepedia.org/arima-harunobu).[1](https://toukenza.jp/en/events/okitanawate) • [2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) Takanobu was killed in the fighting and his army was destroyed, ending Ryūzōji dominance in northern Kyushu and opening the island to Shimazu expansion.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [1](https://toukenza.jp/en/events/okitanawate)
| Key fact | Detail |
|---|---|
| Date | 24th day, 3rd month, Tenshō 12 (1584); English-language accounts give March 24 or May 4, 1584[1](https://toukenza.jp/en/events/okitanawate) • [2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) |
| Place | Okitanawate, a wetland near Shimabara City, Hizen Province (Nagasaki Prefecture)[1](https://toukenza.jp/en/events/okitanawate) • [5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en) |
| Sides | Ryūzōji clan against a Shimazu–Arima coalition[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) |
| Commanders | Ryūzōji Takanobu; Shimazu Iehisa and Arima Harunobu for the coalition[3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) |
| Forces | Ryūzōji about 25,000 (other records give 57,000 or 60,000); allies about 6,000–8,000 or 8,000–10,000 depending on the source[4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89) • [1](https://toukenza.jp/en/events/okitanawate) |
| Outcome | Takanobu killed by the Shimazu warrior Kawakami Tadakata; Ryūzōji army routed[5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en) • [1](https://toukenza.jp/en/events/okitanawate) |
| Consequence | Collapse of Ryūzōji power in northern Kyushu; accelerated Shimazu expansion, followed by Toyotomi Hideyoshi's conquest of Kyushu[1](https://toukenza.jp/en/events/okitanawate) • [4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89) |
## Background and causes
In 1582, Ryūzōji Takanobu (1530–1584), the daimyo of Hizen Province (modern Nagasaki and Saga prefectures), invaded Shimabara to expand his territory.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) Arima Harunobu (1567–1612), the daimyo of Shimabara, could not match him alone and asked [Shimazu Yoshihisa](https://www.edgepedia.org/shimazu-yoshihisa) (1533–1611), the daimyo of Satsuma Province who aimed at unifying Kyushu, for help.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) • [4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89) Yoshihisa put his younger brother Shimazu Iehisa (1547–1587) in charge of the relief army.[3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) • [2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) One heritage account instead names Arima Harunobu and Shimazu Yoshihisa as the leaders of the opposing army.[5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en)
## Course of events
The two armies met on the morning of the battle day at Okitanawate, a wetland that at the time was chest-deep, with only a single narrow path running through it.[5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en) The Ryūzōji army, unfamiliar with the geography, was forced into a hard fight despite its large size.[5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en) In the chaos of battle, Takanobu was killed by the Shimazu warrior Kawakami Sakyonosuke Tadakata.[1](https://toukenza.jp/en/events/okitanawate) • [5](https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en)
When the death of the commander-in-chief reached the battlefield, Ryūzōji morale collapsed and the soldiers, losing all control, fled in a rush.[4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89) Fleeing soldiers packed into the narrow path were cut down one-sidedly by pursuing Shimazu forces.[4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89)
## Conduct of the fighting
Numbers did not decide this battle; terrain and equipment did. The Ryūzōji army of 25,000 men enjoyed a huge numerical advantage, but the Arima–Shimazu force knew the difficult terrain of the battlefield.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) The allies were also equipped with Portuguese weapons that Arima, who had converted to Christianity in 1579, had acquired from the Jesuits.[3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf) • [2](https://www.mlit.go.jp/tagengo-db/R2-00440.html)
One Ryūzōji unit kept order amid the rout. [Nabeshima Naoshige](https://www.edgepedia.org/nabeshima-naoshige)'s column, advancing on the mountain side, was the only one to maintain organized resistance; after learning of the main force's destruction he considered suicide but instead led a desperate retreat, crossing the Ariake Sea by ship from the port of Taira at night to reach his home province.[4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89)
## Outcome and losses
Ryūzōji Takanobu was killed on the field and his army defeated.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf)
To thank the Jesuits for the decisive role they, or at least the weapons they supplied, had played in the victory, Arima ceded the Urakami region to them.[2](https://www.mlit.go.jp/tagengo-db/R2-00440.html) • [3](https://www.mlit.go.jp/tagengo-db/common/001563990.pdf)
## Consequences and political influence
The battle destroyed Ryūzōji dominance in northern Kyushu.[1](https://toukenza.jp/en/events/okitanawate)
## Historians' assessment
The scale of the victory is measured by how quickly the political map changed: a domain that had ruled five provinces saw its rule over northern Kyushu collapse.[6](https://datekatana.jp/zh-TW/events/okitanawate) The sources disagree on the size of the two armies: the Fróis history gives 25,000 for the Ryūzōji, the Hizen Senki 57,000, and Satsuma records 60,000, while allied strength is given as about 6,000–8,000 (Shimazu 3,000; Arima 3,000–5,000) or about 8,000–10,000.[4](https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89) • [1](https://toukenza.jp/en/events/okitanawate) The Western-calendar date is also given differently, as March 24 or May 4, 1584, both corresponding to the lunar date 24th day, 3rd month, Tenshō 12.[1](https://toukenza.jp/en/events/okitanawate) • [2](https://www.mlit.go.jp/tagengo-db/R2-00440.html)
## References
1. Battle of Okitanawate (1584 · Sengoku · Battle) – TOUKENZA. https://toukenza.jp/en/events/okitanawate
2. キリスト教文化遺産群 沖田畷古戦場跡 (MLIT Tagengo database). https://www.mlit.go.jp/tagengo-db/R2-00440.html
3. Stone pillar marking the site of the Battle of Okitanawate (MLIT Tagengo database). https://www.mlit.go.jp/tagengo-db/common/001563990.pdf
4. 沖田畷の戦い（1584） | 合戦 | 戦国 Deep Research. https://deep-sengoku.net/?page=page-kassen-%E6%B2%96%E7%94%B0%E7%95%B7%E3%81%AE%E6%88%A6%E3%81%84%EF%BC%881584%EF%BC%89
5. 沖田畷古戦場跡 (Site of the Battle of Okitanawate), Orasho Hidden Christian Sites in the Nagasaki Region. https://oratio.jp/p_resource/okitanawatekosenjoato?lang=en
6. 沖田原之戰 (1584 · 戰國 · 戰役), DATEKATANA. https://datekatana.jp/zh-TW/events/okitanawate
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*Topic: Encyclopedia › Society and history › History and archaeology › Asian history › Japan › Sengoku and Azuchi-Momoyama Japan (1467 to 1603) › Battles and military campaigns*
*Initially written Sep 24, 2026 · Reviewed: Sep 30, 2026 · Edited: Oct 15, 2026 · Last review: Sep 30, 2026*
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