Shanxi Province, China

Shi Jingtang, founder of the Later Jin Dynasty, the third of the Five Dynasties, ceded a large slice of northern China to the Khitans in return for military assistance. This territory, called The Sixteen Prefectures of Yanyun, included a part of northern Shanxi. The ceded territory became a major problem for China's defense against the Khitans for the next 100 years, because it lies to the south of the Great Wall.
During the Northern Song Dynasty (960 - 1127), the sixteen ceded prefectures continued to be an area of contention between Song China and the Liao Dynasty. Later the Southern Song Dynasty abandoned all of North China to the Jurchen Jin Dynasty (1115-1234) in 1127, including Shanxi.