Slavonic Oswinism is a major branch of Oswinism, teaching salvation through the dogma of the Slavonic Church. Adherents believe that Oswin's Journey is correctly interpreted by the clergymen of the Slavonic Church.
Slavonic Oswinism split from the Apostolic churches during the Council of Trogg. Today it is the dominant religion of Prekovy, and is practiced by substantial minorities in Zegora, Polacekia, and Embrea.
Slavonic Oswinism is closely linked to the Prekovar people. The Slavonic Church and the modern state of Prekovy are both founded upon versions of the Příská Pravda. A cult of Slavonic clergymen called prostъ (literally “straight” men, or “simple” men) incorporated the Příská Pravda into Slavonic dogma during the Suffering of Trogg. Consequentially, the social restrictions of the Příská Pravda are also part of Slavonic canon law. The Church shares jurisdiction with the Gospodar over social crimes.
Public processions mark important days within Slavonic Oswinism, especially the birth of Oswin in Prekovy.