Avvakum

Russian protopope (1620/1621 – 1682)

Avvakum Petrov was a Russian Old Believer and protopope of the Kazan Cathedral on Red Square who led the opposition to Patriarch Nikon's reforms of the Russian Orthodox Church. His autobiography and letters to the tsar and other Old Believers such as Boyarynya Morozova are considered masterpieces of 17th-century Russian literature.

This keyword could refer to multiple things. Here are some suggestions: