History
The northwest is the Bosanska Krajina, the "Bosnian frontier", and for three centuries it was exactly that. The Illyrian Japodes lived around Bihać, which appears in 1260 and became a free royal town of the Hungarian crown in 1262, and it was in the castle of Ključ that the last Bosnian king surrendered to the Ottomans in 1463. Banja Luka, first recorded in 1494, fell in 1528 and became the seat of the Ottoman governors of Bosnia until 1639; Ferhad Pasha Sokolović built the Ferhadija Mosque there in 1579. Bihać held out until 1592. From then on the Una and the Sava were the armed border with the Habsburgs, and every hill town acquired a castle and a captain.
Austria-Hungary took over in 1878. Trappist monks who had settled outside Banja Luka in 1869 gave the town a brewery, a cheese dairy and its first hydroelectric plant, and the authorities planted the avenues that still shade it. In the Second World War the region lay inside the fascist Independent State of Croatia. In the summer of 1942 German and Ustasha forces surrounded the partisans on Kozara and deported thousands of Serb villagers to the camps of Jasenovac and Stara Gradiška, just across the Sava; that November Tito's movement held its first assembly in liberated Bihać.
An earthquake wrecked much of Banja Luka in October 1969, and the centre was rebuilt in concrete. In 1992 the city became the stronghold of the Bosnian Serbs: Bosniaks and Croats were expelled, all of its mosques, the Ferhadija among them, were blown up in 1993, and around Prijedor the camps of Omarska, Keraterm and Trnopolje became known to the world. Bihać and its hinterland endured a three-year siege, complicated by the breakaway fiefdom of the businessman Fikret Abdić at Velika Kladuša, until 1995. The Dayton line left Banja Luka as the seat of Republika Srpska and the Una valley in the Federation. The Ferhadija, rebuilt from its salvaged stones, reopened in 2016.
