Kars (Armenian: Կարս or Ղարս; Azerbaijani: Qars; Kurdish: Qers; Georgian: ყარსი) is a city in northeast Turkey. It is the seat of Kars Province and Kars District. As of 2022, its population was 91,450. Kars, in classical historiography (Strabo), was in the ancient region known as Chorzene (Greek: Χορζηνή), part of the province of Ayrarat in the Kingdom of Armenia, and later the capital of the Bagratid Kingdom of Armenia from 929 to 961. Currently, the mayor of Kars is Ötüken Senger. The city had an Armenian ethnic majority until it was re-captured by Turkish nationalist forces in late 1920.

The city's name may derive from the Armenian word hars, meaning 'bride'. According to another hypothesis, the name derives from the Georgian word kari, meaning 'gate'.

Little is known of the early history of Kars beyond the fact that, during medieval times, it had its own dynasty of Armenian rulers and was the capital of a region known as Vanand. Medieval Armenian historians referred to the city by a variety of names, including Karuts’ k’aghak’ ('Kars city'), Karuts’ berd, Amrots’n Karuts’, Amurn Karuts’ (all meaning 'Kars Fortress'). At some point in the ninth century (at least by 888) it entered into the domains of the Armenian Bagratunis. Kars was the capital of the Bagratid kingdom of Armenia between 929 and 961. During this period, the town's cathedral, later known as the Church of the Holy Apostles, was built.

In 963, shortly after the Bagratuni seat was transferred to Ani, Kars became the capital of a separate independent kingdom, again called Vanand. However, the extent of its actual independence from the Kingdom of Ani is uncertain: it was always in the possession of the relatives of the rulers of Ani, and, after Ani's capture by the Byzantine Empire in 1045, the Bagratuni title "King of Kings" held by the ruler of Ani was transferred to the ruler of Kars. In 1064, just after the capture of Ani by Alp Arslan (leader of the Seljuk Turks), the Armenian king of Kars, Gagik-Abas, paid homage to the victorious Turks so that they would not lay siege to his city. In 1065 Gagik-Abas ceded his kingdom to the Byzantine Empire, but soon after Kars was taken by the Seljuk Turks.

The Seljuks quickly relinquished direct control over Kars and it became a small emirate whose territory corresponded closely to that of Vanand, and which bordered the similarly created but larger Shaddadid emirate centered at Ani. The Kars emirate was a vassal of the Saltukids in Erzurum, whose forces were effective in opposing Georgian attempts at seizing Kars. Thus, it was only in 1206 that Zakare of the Zakarids–Mkhargrdzeli succeeded in capturing Kars, joining it to their fiefdom of Ani.

In 1242, Kars was conquered by the Mongols and later the city fell under Georgian influence. During the reign of David IX of Georgia, the Ilkhanate occupied the southern territories of the Kingdom of Georgia, which included Kars. By 1358, the city was ruled by the Jalayirids and in 1380 it fell to the Qara Qoyunlu. In 1387 the city was leveled and the surrounding countryside was devastated by Timur (Tamerlane). Anatolian beyliks followed for some time after that, until it firstly fell into the hands of the Qara Qoyunlu and subsequent Aq Qoyunlu. After the Ak Koyunlu, as it went naturally for almost all their former territories, the city fell into the hands of the newly established Safavid dynasty of Iran, founded by king Ismail I. Following the Peace of Amasya of 1555 that followed the Ottoman–Safavid War of 1533–1555, the city was declared neutral, and its existing fortress was destroyed.

In 1585, during the Ottoman–Safavid War of 1579–1590, the Ottomans took the city alongside Tabriz. On June 8, 1604, during the next bout of hostilities between the two archrivals, the Ottoman–Safavid War of 1603–1618, Safavid ruler Abbas I retook the city from the Ottomans. The fortifications of the city were rebuilt by the Ottoman Sultan Murad III and were strong enough to withstand a siege by Nader Shah of Persia, in 1731. It became the head of a sanjak in the Ottoman Erzurum vilayet. In July 1744, the city was again besieged by Nader Shah. Later, in August 1745, a huge Ottoman army was routed at Kars by Nader Shah during the Ottoman–Persian War of 1743–1746. As a result, the Turks fled westwards, raiding their own lands as they went.

In 1807, Kars successfully resisted an attack by the Russian Empire. During a break between the Russian campaigns in the region conducted against the Ottomans, in 1821, commander-in-chief Abbas Mirza of Qajar Iran occupied Kars, further igniting the Ottoman–Persian War of 1821–1823. After another Russian siege in 1828 the city was surrendered by the Ottomans on 23 June 1828, to the Russian general Count Ivan Paskevich, 11,000 men becoming prisoners of war. At the end of the war it returned to Ottoman control for diplomatic reasons, Russia gaining only two border forts. During the Crimean War, an Ottoman garrison led by British officers, including General William Fenwick Williams, kept the Russians at bay during a protracted siege, but after the garrison had been devastated by cholera and food supplies were depleted, the town was surrendered to General Muravyov in November 1855.