Answer:
At first, Korea was divided into tribes but eventually organized kingdoms emerged. There were 3 of them, Goguryeo in the north and Silla and Baekje in the south. According to legend Silla was founded in 57 BC by Bak Hyeokgeose, Jumong founded Goguryeo in 37 BC and Onjo founded Baekje in 18 BC.