Baekje was ancient kingdom on the Korean Peninsula from 18 BCE to 660 CE. Baekje was also called Nam Buyeo. According to the Samguk Sagi, a historical record published in ancient Korea, Baekje was founded by Onjo at Wiryeseong (the present-day Han River area in Seoul). Baekje was one of the Three Kingdoms of Korea together with Goguryeo and Silla. Beakje, Goguryeo and Silla tried to expand each of their lands by allying and making war against one another.