Archaeology indicates that the Korean Peninsula was occupied by the Lower Paleolithic period. Korean history begins with the founding of Gojoseon in 2333 BC by the legendary Dan-gun. Following the unification of the Three Kingdoms of Korea under Silla 668 AD, Korea was ruled by the Goryeo Dynasty and Joseon Dynasty. It was annexed by Japan in 1910. At the end of World War II, Korea was divided into Soviet and U.S. zones of occupation. An election was held the U.S. zone in 1948 which led to the creation of the Republic of Korea. Although the United Nations passed a resolution declaring the Republic to be the only lawful government in Korea, the Soviets set up a rival government in the North.