Dongguk Tonggam

This is a book about Korean history ranging from Dangun Joseon (2333 BC?-108 BC) to the end of the Goryeo Dynasty, compiled by Seo Geo-jeong and others at the behest of the king. It is comparable to Zizhi Tongjian (Comprehensive Mirror to Aid in Government) of China. Due to the insufficiency of relevant materials, the period of history from Dangun Joseon to the Proto-Three Kingdoms Period (from after the fall of Dangun Joseon to the 2nd - 3rd centuries AD) was dealt with briefly at the beginning. It is significant that the book mentions Dangun as the founder of the Korean nation.