Emperor Yūryaku
In order to possess Waka, Emperor Yūryaku had Tasa moved out of the way to the distant post of governor of Mimana and made Waka-hime one of his concubines. When Tasa learned that he had been robbed of his wife, he started a revolt looking for help from Silla. Yūryaku, known for his cruelty, ordered Tasa's son, Oto, to lead an army against his father. Oto was joined by a group of men who wanted to secure skilled artisans from Paekche. Oto had settled for several months in Paekche (without taking any action against Tasa or Silla) when he received a message from his father suggesting he hold Mimana and Paekche and break off communication with Japan: