Petrus Särkilahti (a.k.a. Pietari Särkilahti, sometimes written as Petrus Saerkilahti) - died 1529 - was a Finnish student of Martin Luther and one of the early pioneers of teaching science in Finnish language. He spread the idea of the religious reformation eagerly. 
In Turku, Finland, Särkilahti met Mikael Agricola, who became his student. In 1538, the first known books written entirely in Finnish were published by Agricola. Agricola therefore became called by many the father of written Finnish language. Other Finnish language literal works that may have existed from earlier time are assumed to have been burned and destroyed by wars and fires. The earliest extant writing in a Finnic language is a spell written on a birch bark in the beginning of the 13th century AD. 
Already in the 13th century - and perhaps even before - books and other literal works are known to have been published in Finland by churches and monasteries, but nearly all known works from that age have been destroyed by wars and fires as well, and all known books published were written in Latin.
After Särkilahti's death in 1529, it was up to Agricola to continue his work.
- Evangelical Lutheran Church of Finland - Official site