BANJALUKA, DIOCESE of. — City of Bosnia (22,177 inhabitants), capital of the Banate of Urbas (area 20,436 sq. km., population approx. 1,008,000 inhabitants) and seat of the Catholic diocese. Situated precisely in the centre of the Croatian regions, the diocese has an area of 16,520 sq. km., where 134,335 Catholics live among a majority consisting of schismatics and Muslims. It has 6 deaneries and 48 parishes, 36 churches and 120 chapels, 72 Yugoslav and 22 foreign priests. The religious women (the Sisters of Charity of St. Vincent de Paul of Zagreb and the Adorers of the Most Precious Blood, whose principal house was in Nazareth near B.) had, in 1939, 16 convents and 206 sisters (schools and hospitals).
In the period of Roman rule, the regions south of B. depended on the province of Dalmatia and the metropolitan see of Salona (the dioceses of Baloe near Varcar-Vakuf, Sarnada near Kljuc, etc.), while those to the north belonged to the dioceses of the province of Pannonia (Siscia, Cibale, etc.).
In the ancient Croatian State, from the 9th to the 12th century, to which the entire territory of the diocese of B. belonged, there was first the diocese of Nona (Nin), until its abolition in 928, and later also other dioceses, especially those of Zagreb and Knin, whose bishop originally bore the title Episcopus Croatorum or Episcopus croatensis, and finally the archdiocese of Spalato. In the bloody struggles against the Turks from the 15th century onward, and especially after the fall of the Croatian cities of Jajce (1528) and Bihać (1592), the population, once exclusively Croatian and Catholic, was partly exterminated, having been deported or compelled to emigrate, embrace schism, or adopt Islam. Moreover, new masses of people of another faith, led by the Turks, poured in from the southeast to serve as colonizers and guerrilla fighters on the Croatian frontier. Of more than a hundred convents and churches, not a single one survived the Turkish invasion. During the Turkish era, the Bosnian Franciscans cared for the surviving Catholic population, which at that time belonged to the Apostolic Vicariate of Ottoman Bosnia.
The present diocese was founded by the bull Ex hac augusta of Leo XIII on 5 August 1881, as a suffragan diocese of the archdiocese of Vrhbosna in Bosnia. Its first bishop was Josip Garić, appointed only in 1912; previously it had been administered by the metropolitan of Vrhbosna, Josip Stadler, and the titular bishop of Danape, Marijan Marković, who had the cathedral of St. Bonaventure and the episcopal residence built. During the war of 1939–45, as a result of the partisan struggles, the diocese suffered extremely serious damage: churches were destroyed, and part of the population and clergy were dispersed.
The diocese of B. contains the famous abbey of Marija Zvezda (Maria Stella), belonging to the Trappists (5 km from B.), and the Franciscan convents of Lajce and Livno.