Ōsumi Province
The Itō family's most serious rivals in this period were the Shimazu. The Shimazu clan, which had unified Satsuma Province and Ōsumi Province under their control, began to clash with the Itō in 1570. The Itō were finally defeated by the Shimazu in 1578. Yoshisuke, the family head, went to Kyoto by way of Iyo Province, and sought help from Toyotomi Hideyoshi. The family's old lands were restored in 1587, following Toyotomi Hideyoshi's invasion of Kyushu and defeat of the Shimazu clan. By the Edo period, the Itō retained their holdings, which came to be known as the Obi Domain.