The Croatian Orthodox Church was a religious body created during World War II by the Ustasha regime in the Independent State of Croatia (NDH), as part of their attempt to suppress Serbian culture within the territory controlled by the NDH. It existed from 1942 to 1945, and was intended as a national church to which Serbs living in Croatia would be forced to convert, thus making it possible to describe them as "Croats of Orthodox faith". It had little or no popular support. It was only recognized by one other Orthodox church, the Romanian Orthodox Church, on August 4, 1944(at the time, Romania was also under the control of a Fascist regime) Its manager was Savić Marković Štedimlija.
There were some discussions during the 1990s, after the break-up of SFR Yugoslavia, regarding the revival of such a church.
It's leader was Germogen, Metropolitan of Zagreb, a priest of the Russian Orthodox Church Outside Russia, who is said to have had Uniate sympathies. Most of the church's priests were Serbian priests who were compelled to change churches in order to survive, together with defrocked Orthodox priests, émigré priests from Russia, and some Uniate and Roman Catholic priests.
The church did not function as a regular church and was essentially a political tool of the Ustasha. It was meant to be temporary, since the eventual goal of the Ustasha regime was the establishment, within ten years, of a theocratic and purely Catholic state. The church was formed by a government statute (No. XC-800-Z-1942) on April 4, 1942. On June 5, using the statute issued by the government, the church's constitution was passed. On June 7 Germogen became the first and only Orthodox Metropolitan of Zagreb. The church lasted until the NDH collapsed, as the Partisans started to take over. Germogen was shot to death the same day the partisans entered Zagreb.
The main reason for the creation of this Church was to make a concession to the Serbian population, as some in the Ustasha leadership felt this would decrease the will to rebel in Serbs. Another possible reason was an attempt among some Croats to distinguish between Serbian nationality and Orthodox faith, as a sign of respect to the founders of the "Party of Rights" (now known as Croatian Party of Rights) from which the Ustasha movement developed. The Ustasha evolved from this party's extremist wing after the King of Yugoslavia banned all political parties in 1929. The two main founders of the Party of Rights, Ante Starčević and Eugen Kvaternik, were not antagonistic towards Orthodoxy, although they were to a large degree anti-Serb. Ante Starčević's mother was Orthodox, and Kvaternik had promoted in the early days of the party the creation of an Orthodox Patriarch in Croatia.
Before the Croatian Orthodox Church was formed by the Ustasha, the NDH officially described the Eastern Orthodox Church as the "Greek-Eastern Church", and would refer to it as the "Schismatic Church" or the "Greek non-Uniate Church". The Ustasha wanted to make their church seem legitimate; they asked for recognition from the Ecumenical Patriarch in Istanbul, but this was almost immediately rejected. They were forced to abandon plans to establish a monastery on Mount Athos to add to their legitimacy.
In the 1990s there were reports that the Croatian president after Operation Storm was planning to create a Croatian Orthodox Church, because the Serb population had been forced out by Ustase (Croatians) and most churches, monasteries and religious structures in Croatia that were associated with the Orthodox Church were destroyed by Croatians. There is much evidence to support this, since Croatian leadership would have likely known that such an action would create a negative image of Croatia abroad. The evidence in support of this, is when HRT (Croatian Radio Television) aired several segments on TV in which they mentioned monasteries in Croatia as belonging to the Croatian Orthodox Church. Dr. Adalbert Rebic, Dean of the Theological College in Zagreb, appeared on a show in which he called for the creation of such a church.