Date Masamune
Although the Sōma were a minor regional power, their territory was sandwiched between the much more powerful Satake clan to the south and the Date clan to the north. The Date under Date Masamune were especially aggressive and expansionist, and despite efforts by the 16th hereditary chieftain Sōma Yoshitane to remain aloof of the conflicts of the Sengoku period, the Date invaded his domain on 30 occasions. Both Sōma Yoshitane and Date Masamune submitted to Toyotomi Hideyoshi at the Siege of Odawara.