Since Finnish was not an official language in Finland until 1863, most records were written in Swedish. To do research in these records, you will need to know some Swedish and Finnish key words and phrases. Also, be aware that Orthodox church records were written in Russian until after Finnish independence.
https://www.familysearch.org/wiki/en...t7h5AWVLqqxjtU
https://www.familysearch.org/wiki/en...t7h5AWVLqqxjtU