Daugavpils (see also other names) is a state city in southeastern Latvia, located on the banks of the Daugava River, from which the city derives its name. The parts of the city to the north of the river belong to the historical Latvian region of Latgale, and those to the south lie in Selonia. It is the second-largest city in the country after the capital Riga, which is located some 230 kilometres (143 miles) northwest and is the ninth most populous city in the Baltic states.

Daugavpils is located relatively close to Belarus and Lithuania (distances of 33 km (21 mi) and 25 km (16 mi), respectively), and some 120 km (75 mi) from the Latvian border with Russia. Daugavpils is a major railway junction and industrial centre, and was an historically important garrison city lying approximately midway between Riga and Minsk, and between Warsaw and Saint Petersburg.

Daugavpils, then called Dyneburg, was the capital of Polish Livonia while in Polish–Lithuanian Commonwealth. Following the first partition of Poland in 1772, the city became part of the Russian Empire. Since the Second World War, it has maintained an overwhelmingly Russian-speaking population, with Latvians and Poles being significant minorities. Historically, German and Yiddish were additional prominent native languages.

In the Latvian language, the current name Daugavpils (Latvian pronunciation: [ˈdauɡaupils] ^ⓘ) references Daugava and the Latvian word pils (meaning "castle" - cognate with Lithuanian pilis, with Greek polis and with Old Prussian pils).

Historically, several names in various languages have identified Daugavpils. Some are still in use today.

The town's history began in 1273 when the Livonian Order, led by Ernst von Ratzeburg, built the Dünaburg Castle on the site of a Lithuanian settlement of Naujinis (about 18 km from present-day Daugavpils). Between 1281 and 1313, Lithuania ruled Daugavpils, the lands up to Daugava and its surroundings. In 1561 it again became part of the Grand Duchy of Lithuania and, subsequently, of the Polish–Lithuanian Commonwealth in 1569 (see Duchy of Livonia). In 1621 Daugavpils became the capital of the newly formed Inflanty Voivodeship, which existed until the First Partition of Poland (1772). In 1577 the Russian tsar Ivan the Terrible captured and destroyed Dünaburg castle.

That same year, a new castle and a town were built 20 km (12 mi) downriver, by the Polish King and the Grand Duke of Lithuania Stephen Báthory. In 1582 Daugavpils was granted Magdeburg town rights. In 1654, Russia invaded Polish-Lithuanian Commonwealth, seizing much of the eastern lands. Russian troops besieged Daugavpils in April and May 1655, but did not capture the city; it was only taken by Swedish troops on July 11, 1655, who invaded Poland at that time. When the Russo-Swedish war started, the Russians captured Daugavpils on 10 August 1656, renamed the town Borisoglebov and controlled the region for 11 years, between 1656 and 1667. Russia returned the area of Latgale to Polish–Lithuanian Commonwealth following the Treaty of Andrusovo (1667). Called Dyneburg, the city became the capital of the Inflanty Voivodeship, also known as the Duchy of Livonia, and the starostwo of Dyneburg. It was a place of local sejmik's gatherings. Roman Catholic Bishop of Inflanty, who was always residing outside of diocese, moved his seat to Dyneburg at the end of 17th century. At the end of the 18th century, 540 people lived in the city itself, but counting the population of the suburbs the number was 1,373.

It became part of the Russian Empire after the First Partition of Poland in 1772. It was the uyezd administrative center as part of the Pskov Governorate (1772-1776), Polotsk (1776-1796), Belarusian (1796-1802), and finally Vitebsk (1802-1917), first as Dinaburg, then Dvinsk later during Russian rule.