Western Rite parishes and monasteries exist within certain jurisdictions of the canonical Eastern Orthodox Church, predominantly within the Russian and Antiochian jurisdictions in North America, with the latter having created an Antiochian Western Rite Vicariate (AWRV).
In addition, the Western Rite is practices within religious communities outside the main Eastern Orthodox Church. The Communion of Western Orthodox Churches and the Orthodox Church of France are entirely Western Rite. Furthermore, there is a small number of Western Rite communities among the Old Calendarists, such as the former Western Rite Exarchate of the Holy Synod of Milan and the Autonomous Orthodox Metropolia of North and South America and the British Isles. In the past, there have also been Western Rite communities within Oriental Orthodoxy.
Western Rite parishes are found almost exclusively in countries with large Roman Catholic or Protestant (particularly Anglican) populations. There are also numerous devotional societies and publishing ventures related to the Western Rite. Despite having a place within many Eastern Orthodox jurisdictions, the Western Rite remains a contentious issue for some.
In the times prior to theological disputes that arose between 9th and 11 century, Byzantine Rite churches of the East and Latin Rite churches of the West were in full communion, confessing the same Orthodox, Catholic Christian faith. In the East, the Byzantine Rite was the predominant liturgical rite. In the West, the Latin Rite was the dominant rite. In the time of the final East–West Schism of 1054, most of the Churches that remained in communion with four Eastern Patriarchates used the Byzantine Rite, though there were still regions where other liturgies, including the Roman Rite, were used. One of such regions was Byzantine (southern) Italy.
In the time of the final split (1054) much of the southern Italy was still under Byzantine rule and was organized as the Catepanate of Italy. For centuries, church life in Byzantine regions of Italy was developing under dual influence of Latin and Byzantine traditions. During the 11th century, Latin rite churches in Byzantine Italy still did not use the interpolated Creed (Filioque) and were in full communion with Eastern Orthodoxy. During the Byzantine–Norman wars, Byzantine Empire finally lost its last positions in the West. The Norman conquest of southern Italy was completed with the Conquest of Bari in 1071. One of the main consequences of the political change was the establishment of the supremacy of the Church of Rome over the church life in former Byzantine Italy. The main theological challenge was resolved at the Council of Bari in 1098. From that point, all churches in southern Italy were obligated to accept the Filioque clause into the Creed. Implementation of that decision soon marked the end of Latin rite Orthodoxy in southern Italy.