The earliest northern Korean kingdom, founded in the later 1st millennium BCE, was Gojoseon while, in the south, the Jin kingdom dominated in the 2nd and 3rd centuries BCE. In 108 BCE the Chinese Han dynasty defeated Gojoseon, bringing about the Proto-Three Kingdoms era, comprising a series of small independent states, notably the southern states of Pyonhan, Mahan and Chinan. Following invasion, the Han established four commanderies (provinces) with Chinese governors and colonists living there, but three soon fell or retreated. The Lo-Lang Commandery, however, lasted over 400 years on the Korean peninsula, and disseminating Chinese influence including new art forms, advances in technology, and social practices and customs. The smaller states soon emerged as three separate kingdoms – Koguryo (37 BCE–688 CE), Paekche (18 BCE–600 CE) and Shilla (57 BCE–935 CE) – bringing about the era of the Three Kingdoms. This was a time of rivalry and conflict, with each kingdom frequently swapping allegiances with their powerful neighbours, Japan and China.
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