https://en.wikipedia.org/wiki/Three_Kingdoms_of_Korea
Samhan or the Three Kingdoms of Korea (Korean: 삼국시대; Hanja: 三國時代; RR: Samguk-sidae) refers to the three kingdoms of Goguryeo (고구려, 高句麗), Baekje (백제, 百濟), and Silla (신라, 新羅). Goguryeo was later known as Goryeo (고려, 高麗), from which the modern name Korea is derived. The Three Kingdoms period is defined as being from 57 BC to 668 AD (but …