After the death of Hideyoshi, one of the Council of Five Elders, Ieyasu TOKUGAWA and Masamune broke the last will and testament of Hideyoshi, by setting up the engagement between Irohahime, the first daughter of Masamune, and Tadateru MATSUDAIRA, the 6th son of Ieyasu in 1599.
秀吉の死後、五大老・徳川家康と政宗は秀吉の遺言を破り、慶長4年（1599年）、政宗の長女・五郎八姫と家康の6男松平忠輝を婚約させた。