Roman times river's left tributary, the
Krupa, in a protected area 30 kilometers upstream from the city The history of inhabitation of the area of Banja Luka dates back to ancient times. There is substantial evidence of
Roman presence in the region during the first few centuries A.D., including the "Kastel" () fort in the centre of the city. The area comprising Banja Luka was entirely in the kingdom of Illyria and then a part of the Roman province of
Illyricum, which was split into the provinces of
Pannonia and
Dalmatia, of which Castra became a part. Ancient Illyrian maps refer to the settlement in Banja Luka's present-day location as
Ad Ladios, a settlement located on the river
Vrbas.
Middle Ages Slavs settled in the Balkans in the 6th century. Mediaeval fortresses in the vicinity of Banja Luka include Vrbas (1224), Župa Zemljanik (1287),
Kotor Varoš (1323), Zvečaj (1404), and Bočac (1446). In one document written by King
Vladislav II on 6 February 1494, Juraj Mikulasić was mentioned as
castellan of Banja Luka. Below the town was a smaller settlement with one Catholic monastery.
Ottoman rule , also known as the
Ferhadija Mosque Banja Luka fell to the
Ottomans in 1527. It became the seat of the
Sanjak of Bosnia sometime before 1554, until 1580 when the
Bosnia Eyalet was established. Bosnian beylerbeys were seated in Banja Luka until 1639.
Ferhad Pasha Sokolović, a relative of Grand Vizier
Mehmed-pasha Sokolović, had, upon his return to Bosnia in 1574, begun the building of over 200 buildings ranging from artisan and sales shops to wheat warehouses, baths, and mosques. Among the more important commissions were the
Ferhadija and
Arnaudija mosques, during whose construction plumbing infrastructure was laid out, which served the surrounding residential areas. This stimulated the economic and urban development of Banja Luka, which soon became one of the leading commercial and political centres in Bosnia. It was also the central sanjak in the Bosnia Eyalet. In 1688, the city was burned down by the Austrian army, but it quickly recovered. Later periodic intrusions by the Austrian army stimulated military developments in Banja Luka, which made it into a strategic military centre. Orthodox churches and monasteries near Banja Luka were built in the 19th century. In the 19th century,
Sephardic Jews and
Trappists migrated to the city and contributed to the early
industrialization of the region by building mills, breweries, brick factories, textile factories, and other important structures. The
Trappist monastery built in the 19th century lent its name to the neighbourhood of
Trappisti and has left a significant legacy in the area through its
Trappist cheese and its
beer production. In 1835 and 1836, during Ottoman administration, numerous people from Banja Luka emigrated to
Lešnica,
Lipnica, and
Loznica, the villages around Loznica, and to
Šabac. The Ferhadija Mosque, built in 1579, was demolished in 1993 during the
Bosnian War. It was rebuilt in 2016.
Austro-Hungarian rule Despite its leading position in the region, Banja Luka as a city was not modernised until the
Austro-Hungarian occupation in the late 19th century. Railroads, schools, factories, and infrastructure were constructed and developed, which turned Banja Luka into a modern city.
Yugoslavia , built in 1929 After World War I, the town became the capital of the
Vrbas Banovina, a province of the
Kingdom of Yugoslavia. The provincial capital owed its rapid progress to the first Ban Svetislav Milosavljević. During that time, the
Banski dvor and its twin sister, the Administration building, the Serbian Orthodox Church of the Holy Trinity, a theatre and a museum were built, the Grammar School was renovated, the Teachers College enlarged, a city bridge was constructed, and the park renovated. 125 elementary schools were functioning in Banja Luka in 1930. The revolutionary ideas of the time were incubated by the "Pelagić" association and the Students' Club. Banja Luka naturally became the organisational centre of anti-fascist work in the region.
World War II During World War II, Banja Luka was occupied by
Axis troops and was included in the
Independent State of Croatia, a
Nazi puppet-state led by
Pavelić's
Ustaše. Most of Banja Luka's Serbs and Jews were deported to concentration camps such as
Jasenovac and
Stara Gradiška. The Jasenovac camp was one of the largest
extermination camps in Europe, which was notorious for its high mortality rate and the barbaric practices that occurred in it. On 7 February 1942, Ustaše paramilitaries, led by a Franciscan friar,
Miroslav Filipović (aka Tomislav Filipović-Majstorović),
killed more than 2,300 Serbs (among them 500 children) in
Drakulić,
Motike, and
Šargovac (a part of the Banja Luka municipality). The city's
Cathedral of Christ the Saviour and Orthodox church of the Holy Trinity were totally demolished by the Ustaše, as was the Church of St. George in
Petrićevac. The
Bishop of Banja Luka,
Platon Jovanović, was arrested by the Ustaše on 5 May 1941 and was tortured and killed afterwards. His body was thrown into the
Vrbanja river. The city was liberated by the
Yugoslav Partisans on 22 April 1945.
1969 earthquake On 26 and 27 October 1969, two devastating earthquakes (6.0 and 6.4 on the
Richter scale) damaged many buildings in Banja Luka. Around 20 to 23 people were killed, and over a thousand were injured. A large building called Titanik in the centre of the town was razed to the ground, and the area was later turned into a central public square. With contributions from all over Yugoslavia, Banja Luka was repaired and rebuilt. During this period, a large Serb population moved to the city from the surrounding villages and from more distant areas in Herzegovina.
Bosnian War Even though there were no open hostilities between the warring sides in Banja Luka, the city's Bosniak and Croat populations were systematically intimidated, harassed, tortured, their property was seized, and the city was ethnically cleansed.
1994 Banja Luka incident On 28 February 1994, an incident occurred in which four
Republika Srpska Air Force aircraft, which had violated Bosnia's no-fly zone and bombed a factory, were shot down southwest of Banja Luka by planes from the
United States Air Force on behalf of
NATO, marking the first active combat action in the alliance's history. ==Demographics==