North Korea, officially the Democratic People's Republic of Korea, is a country in East Asia, in the northern part of the Korean Peninsula. The name Korea is derived from Goryeo, a dynasty which ruled in the Middle Ages. The capital and largest city is Pyongyang. North Korea shares a land border with China to the north and north-west, along the Amnok and Tumen rivers. A small section of the Tumen River also forms North Korea's short border with Russia to the northeast. The Korean Demilitarized Zone marks the boundary between North Korea and South Korea. The legitimacy of this border is not accepted by either side, as both states claim to be the legitimate government of the entire peninsula.
Korea was governed by the Korean Empire from the late 19th century until it was annexed by the Empire of Japan in 1910. When Japan surrendered at the end of World War II in 1945, Korea was divided into two occupied zones, with the north occupied by the Soviet Union and the south by the United States. Negotiations on unification failed, and in 1948 two separate government were formed: the Democratic People's Republic of Korea in the north, and the Republic of Korea in the south.