Bosanska Krajina

In the 6th century, today's northwestern Bosnia was part of the Roman province of Dalmatia. It fell under the jurisdiction of the Eastern Roman Empire. Shortly thereafter, Eurasian Avars and their Slavic subjects from central-eastern Europe invaded Dalmatia and settled in what is now Bosnia and Herzegovina. In the 7th century the Serbs and Croats formed principalities initially under the Eastern Roman Empire. The region was part of the Duchy of Croatia in the Early Middle Ages.[6] which later became part of the Kingdom of Croatia under Tomislav I[7]

Archaeological data show that cemeteries of northwestern Bosnia clearly indicate that from the first half of the 10th century this territory was under political rule of the Croatian ruler.[8]

Northern parts of the territories were part of Slavonian Banate (parishes Sana, Vrbas and Dubica, and Lower Pounje was part of Zagreb parish) as lower S(c)lavonia, where parish Sana served as seat of Babonić family (later Blagajski), and southern were parts of Pset and Pliva parish.

In the 13th and 14th century, from Pliva parish, a region called Donji Kraji, located in today's southern Bosanska Krajina developed, and was first mentioned as a property of the Diocese of Bosnia and claimed by the Bosnian Banate.

By the 14th century, the Ottoman Empire had significantly expanded into the western Balkans in a series of wars, and the Turkish westward incursions eventually made this region an Ottoman borderland. Jajce had fallen to the Ottomans in 1463, marking the downfall of the Kingdom of Bosnia, although was later taken from the Ottomans and organized as defensive Banate of Jajce. The Battle of Krbava Field in 1493 effectively ended the Kingdom of Hungary's persistent hold over the entire region, restricting them to fortified cities, and when Jajce fell again in 1528, Ottoman rule persisted almost till the end of 19th. century.

In the late 15th century, a local Croatian lord (knez) Juraj Mikuličić erected a fort in the village of Bužim near Bihać, fearing the advancing Ottoman army. Mikuličić died in 1495, but the Bužim fort would not pass to Ottoman control until 1576.[9]

After the crucial 1526 Battle of Mohács and the 1527 election in Cetin, Croatia became part of the Austrian Habsburg Empire. The Ottoman Empire formally established the Eyalet of Bosnia in 1580. The Croatian lands in general were reduced to a fraction of what they encompassed, and only the westernmost parts of today's Bosanska Krajina still resisted the Ottoman rule. Nevertheless, the Ottoman armies preferred to advance towards their targets in the northwest through more easily passable terrain, such as along the river Danube, for example Vienna was first besieged in 1529 after the army had gone through Osijek, Mohács and Buda. The natural obstacles in and around the region, especially at the time, included the rivers Sava, Vrbas, Una and Sana, as well as the mountains such as Plješevica, Šator, Klekovača, Raduša, Grmeč, Kozara and Vlašić.

Turkish incursions expanded further to the north, and Charles of Styria erected a new fortified city of Karlovac in 1579. In 1580 the Turks responded by declaring the Pashaluk of Bosnia which unified all the Sanjaks, including territory in modern-day Croatia. As a result of the wars and border changes, the Catholic Croat population moved north, and was replaced with Orthodox Serbs.[10]

The Bužim fort, under Ottoman control since 1576, was successfully held by the Ottomans in numerous battles (1685, 1686, 1688, 1737) and it was also upgraded (1626, 1834) until their eventual surrender in the 19th century. The building remains to this day as a monument to the Ottoman conquest.[9]

Bihać held out longer than Bužim; it was a free royal city and at one time the capital of the Kingdom of Croatia (metropolis et propugnaculum totius regni Croatiae).[11] But, in 1592 the Turkish army of about 20,000 under Hasan-pasa Predojević, an Ottoman vizier, attacked and forcefully occupied Bihać. Records show that nearly 2,000 people died in defense of Bihać, and an estimated 800 Croat children from Bihać were sent into servitude in Turkey, to be educated in Islam and become Yenicari. Hasan-pasha Predojević pressed further north into Croatia, but was defeated in the June 1593 Battle of Sisak.

When the Ottoman Empire lost the 1683–1690 War of the Holy League to the Habsburg Monarchy and her allies, and ceded Slavonia and Hungary to Austria at the 1699 Treaty of Karlowitz, the northern and western borders of the Sanjak of Bosnia (corresponding largely to the modern Bosnian borders), became a permanent frontier between the Austrian and Ottoman empires. The Ottomans wanted to turn the tide of warfare to their side, so, opposite to the Habsburg Military Frontier, they formed a Bosnian Frontier which was in the Military Frontiers like, split on captains, each having its own fortifications and military regiments.

The Krajina was further settled by Serbian herders, who served as militia, defending it from hostile incursions and maintaining order, or as medics and workforce for the much needed frontline with the Austrian Empire. Since then, the Serbs formed the majority of Bosanska Krajina's population.

In mid-1858, an uprising known as Pecija's First Revolt broke out in the region, resulting from Ottoman pressure against the local Serb populace. It was crushed by December.

The Bosnian Frontier, like the rest of Bosnia and Herzegovina, participated in the 1875 – 1878 Herzegovina Uprising.

Monument to the Revolution, dedicated to the victims of the Kozara Offensive and the aftermath

During World War II, Bosanska Krajina was known for its very strong resistance to the Fascist regime. The anti-fascist Partisan movement in the Bosanska Krajina region was more ethnically diverse than in any other part of former Yugoslavia during World War II. In the winter of 1942/1943 the Partisans established the Republic of Bihać in Bosanska Krajina. Soon afterwards, Bosanska Krajina was also the place of historical agreements that have taken place in Jajce and Mrkonjić Grad in 1943, ones that established the Republic of Bosnia and Herzegovina in its current borders, as well as the Federation of Yugoslavia.

During World War II the Ustasha Jasenovac concentration camp was established just across the river Sava from Bosanska Krajina, and many of the region's inhabitants (mainly Serbs, Romani and Jews but also some communist Bosnian Muslims and Croats) were killed there.

During the 1992-95 Bosnian War, Bosanska Krajina was divided between Republika Srpska, the Republic of Bosnia and Herzegovina, and the Autonomous Province of Western Bosnia. The Serb entity of SAO Bosanska Krajina was established in summer 1991. The region was also a place of concentration camps, including Manjača and Omarska where predominantly Bosniaks were held, tortured, raped, and killed.

For the past two years, non-Serbs in the Bosanska Krajina area have been "cleansed" through systematic persecution that includes torture, murder, rape, beatings, harassment, de jure discrimination, intimidation, expulsion from homes, confiscation of property, bombing of businesses, dismissal from work, outlawing of all scripts except the Cyrillic in public institutions, and the destruction of cultural objects such as mosques and Catholic churches.

— Human Rights Watch report 1994[13]