Novatian

https://en.wikipedia.org/wiki/Novatian

Novatian (c. 200–258) was a scholar, priest, and theologian. He is considered by the Catholic Church to have been an antipope between 251 and 258. Some Greek authors give his name as Novatus, who was an African presbyter.

He was a noted theologian and writer, the first Roman theologian who used the Latin language, at a time when there was much debate about how to deal with Christians who had lapsed and wished to return, and the issue of penance. Consecrated as pope by three bishops in 251, he adopted a more rigorous position than the established Pope Cornelius. Novatian was shortly afterwards excommunicated: the schismatic church which he established persisted for several centuries (see Novatianism).