The first Catholics of the Byzantine rite in what was Yugoslavia were Serbians living in Croatian territory under Hungarian control in the early 17th century. In 1611 they were given a bishop, who was officially the Byzantine vicar of the Latin Bishop of Zagreb. His headquarters was at March monastery, which became a center of efforts to bring Serbian Orthodox into communion with Rome.

After a period of tension with the local Latin bishops, the Serbs in Croatia were given their own diocesan bishop by Pope Pius VI on 17 June 1777, with his See at Križevci. He was made suffragan, at first, to the Primate of Hungary, and later (1853) to the Latin Archbishop of Zagreb.

The diocese of Križevci was extended to embrace all the Byzantine Catholics in then-Yugoslavia when this new country was founded after World War I. Thus the diocese included 5 distinct groups: some ethnic Serbs in Croatia, Croatians, Ruthenians who had emigrated from Slovakia around 1750, Ukranians who emigrated from Galicia in about 1900, Macedonians in the south of the country who became Catholic because of 19th c. missionary activity (who now have their own Apostolic activity), and a few Romanians in what was called the Yugoslavian Banat.

Interestingly, Blessed Aloysius Cardinal Stepinac, the Archbishop of Zagreb tried to save Serb converts to the Church from the murderous pro-Nazi Croatian Ushtashi. The present Bishop of Križevci for about 50,000 Byzantine Catholics in former Yugoslavia is Bishop Slavomir Mkilovs who was appointed in 1983 and resides in Zagreb, capital of Croatia.

After the breakup of Yugoslavia into several independent republics in 1991, new arrangements were necessary for the Greek Catholics in the region. In 2001 an Apostolic Exarchate was established for Greek Byzantine Catholics in the Former Yugoslav Republic of Macedonia, headed by the Latin Bishop of Skopje, presently Kiro Stojanov (born 1959, appointed 2005). It now has five parishes and 11,491 faithful.

In 2003 an Apostolic Exarchate was created for Greek Catholics in Serbia and Montenegro, headed by Bishop Djura Džudžar (born 1954, appointed 2003). It has 21 parishes and 22,720 faithful, consisting mostly of a group of ethnic Rusyn Greek Catholics in the region of Vojvodina.

The diocese of Križevci now includes Croatia, Slovenia and Bosnia-Herzegovina. Headed by Bishop Nikola Nino Kekić (born 1943, appointed 2009), it has 21,480 faithful in 44 parishes. Since 1966 the diocesan offices have been located in Zagreb.

Last Modified: 30 Mar 2012