Nanjing was the name for modern Beijing during the Khitan-led Liao dynasty of China, during which it served as the empire's southern capital. To distinguish "Nanjing" (literally 'southern capital') from the modern city of Nanjing in Jiangsu, and Beijing Damingfu, the name for modern Daming County in Hebei Province during the Northern Song dynasty, Chinese historians sometimes refer to Liao-era Beijing as Liao Nanjing (辽南京; 遼南京). The Liao acquired the city, then known as Youzhou, in the cession of the Sixteen Prefectures in 938 by the Later Jin, one of the five short-lived dynasties that ruled northern China following the end of the Tang dynasty. The city was officially renamed "Nanjing, Youdu Fu" (南京幽都府). In 1012, the city was renamed "Nanjing, Xijin Fu" (南京析津府). The city was also colloquially referred to at the time as "Yanjing". In 1122, the city was captured by the Jurchen-led Jin dynasty (1115–1234)—who officially renamed it "Yanjing", ending the use of "Nanjing" for what is today modern Beijing.