During the Sengoku period (1467–1568), clans across Japan battled for regional supremacy. In 1584, the combined forces of the Arima and Shimazu clans, numbering only 8,000 soldiers, defeated the 50,000-strong army of the Ryuzoji clan. The Arima and Shimazu cleverly used the hilly terrain of Okitanawate to give themselves the advantage they needed to win.