Iga–Kōka alliance

In the Sengoku period of Japan, the adjacent Iga ikki and Kōka ikki, self-governed military confederations of ninja families in the respective regions of Iga Province and Kōka District, frequently allied in mutual defense against outside military threats. The alliance is first attested in 1487 at the Battle of Magari. A constitutional document with an approximate date of 1560, and attributed to Iga, formalized the alliance between Iga and Kōka. Governance of the alliance, as specified in the constitutional document, constituted of 10 military commissioners (bugyo) from Iga and 12 from Kōka, who would meet along the border of the two ikki. The alliance of the two ikki was effectively terminated when Kōka surrendered to the forces of Oda Nobunaga on March 27, 1574.