Battle of Baekgang
Uija, the last king of Baekje (reigned 641–660), formed an alliance with Japan and made Prince Buyeo Pung and King Zenko stay there as their guests. In 660, Baekje fell when it was attacked by Silla, who was in alliance with Tang China. Former generals of Baekje, including Gwisil Boksin, asked Japan to return Prince Buyeo Pung and requested military aid. In 663, Japan, supporting Baekje, was defeated by the allied forces of Silla and Tang China in the Korean Peninsula (the Battle of Baekgang), and the restoration of Baekje ended up in failure. After the fall of Baekje, Japan took in many Baekje Korean refugees who were mainly craftspeople, architects and scholars who played a major role in the social development of Japan during that period. While at the same time hostility between Japan and Silla escalated. Empress Jitō honored King Zenko by giving him the hereditary title of Kudara no Konikishi and allowed him to pass on his royal lineage to future generations. According to the , Takano no Niigasa came from a background of the naturalized clansmen and was a 10th-generation descendant of King Muryeong of Baekje. She was chosen as a wife for Emperor Kōnin and subsequently became the mother of Emperor Kanmu.