Goguryeo
Goguryeo also later known as Goryeo, was a Korean kingdom which was located on the northern and central parts of the Korean Peninsula and the southern and central parts of modern-day Northeast China. At its peak of power, Goguryeo encompassed most of the Korean Peninsula and large parts of Manchuria, along with parts of modern-day Russia. Archaeological evidence suggests it may have extended as far west as modern-day eastern Mongolia.
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