Catholic Slavs

Catholic Slavs and Slavic Catholic are terms used for the historically and/or predominantly Catholic Slavic nations and the history of Catholicism among the Slavic peoples; especially amongst the Western Slavs. The Catholic Slavic nations include all West Slavs (Poles, Czechs and Slovaks and all their sub-ethnicities ex. Kashubs, Silesians) as well as the westernmost South Slavs (Slovenes and Croats).

Grand Duke Kazimierz IV of Lithuania and Poland (r. 1440–92) initiated the Catholicization of Kiev (which was Orthodox) early in his reign.

The Union of Brest (1596) saw the official establishment of the Uniate Church (Eastern it custom and ritual but subscribing to Catholic dogma and submission to the Pope as head of the Church) in the Grand Duchy of Lithuania.

The Habsburg Monarchy launched a programme of re-Catholicization in Bohemia and Moravia in the 1620s. The Serbian Orthodox Eparchy of Marča became Uniate in 1611, although it was part of a conflict between local Catholic and Orthodox clergy over the century.

Modern countries in which historically Catholic Slavs form a majority or otherwise such nation states include:

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