The seat of an independent Armenian principality during the 9th and 10th centuries, Kars was captured by the Seljuqs in the 11th century. Taken by the Mongols in the 13th century and by Timur (Tamerlane) in 1387, it was incorporated into the Ottoman Empire in 1514. After withstanding a siege by Iranians in 1731 and successfully resisting the Russians in 1807, it fell to the Russians in 1828 and 1855 and was formally annexed by Russia in 1877–78. It was returned to Turkey in 1918, though the Soviet Union later (1945–47) tried unsuccessfully to reclaim it as part of the Armenian S.S.R.

Kars's historical buildings include Kümbet Camii (“Church of the Apostles”), an Armenian church that was converted into a mosque; a bath dating from the Ottoman period; and an old citadel overhanging the river that was once a strong military post (probably late 16th century). Kars is important as a centre for trade in livestock and is also noted for its cheese. It also produces coarse woolens, carpets, and felts. An important military station, it is linked by rail and road with the principal Turkish cities.

The region around Kars was part of the Armenian kingdom in antiquity and contains a number of sites dating from that period. Ani, east of Kars city and near the Armenian frontier, was the Bagratid capital in the 10th century. Pop. (2000) 78,473.