Sangju has played an important role in much of
Korean history. It first emerged after the
Silla conquest of the area, in which minor states such as
Goryeong Gaya (in
Hamchang-eup) and
Sabeol-guk (in
Sabeol-myeon) were subjugated. The dates at which these conquests occurred are open to debate, but it is clear that the area was under firm Silla control by 505, and probably for some time before then. Under Silla, the fortress of Sangju was one of the nine
ju, or provincial administrative units, into which the portions of the kingdom near
Gyeongju were divided. It played a critical role in regulating traffic along the east–west transit route which connected the
Han River valley in the west (which Silla acquired in 553) with Gyeongju area. It would have been the first major city that
Buddhist missionaries from
Goguryeo would have reached when travelling down from
Haneuljae Pass in the 6th century. During the tumultuous decline of
Unified Silla in the late 9th century, a number of rebellions occurred in Sangju, as they did throughout the country. Notable among them are the rebellions of
Ajagae, who seized the fortress of Sangju and declared himself a general, and the Silla noble
Bak Eon-chang, who established the kingdom of
Sabeol-guk in the Sabeol-myeon area until he was defeated and overthrown by the
Later Baekje leader
Kyŏn Hwŏn in 927. Ajagae surrendered to
Wang Kŏn in 918. In 1895, as part of a general reorganization of local government, Sangju was designated Sangju-gun (Sangju County). In 1914, its boundaries were extended to cover Hamchang County, present-day Hamchang-eup. On January 1, 1986, separate administrative divisions were created for the city center (which was called Sangju City) and the outskirts (which continued to be called Sangju County). On January 1, 1995, the city and county were reunified to create the present-day entity of Sangju City. Under
Japanese occupation, the occupation government made various efforts to modernize local agriculture and resource extraction. The railroad through Sangju was completed in 1924, and around the same time the agricultural-training institution which would become Sangju National University was established. In 2002, the first
Carthusian monastery in Asia was established in the city, the
Charterhouse Our Lady of Korea. ==Government==