The church stands on the former site of a wooden church. The abundance of brick in the decor reflects the prestige of the place, which houses one of the country's most precious medieval relics: the shrine of Bishop Henry. He was killed in 1156 by a peasant called Lalli and buried in his church. The marble tomb (15C) was donated by Magnus II Tavast and the brass plaque that covers it shows Henry, his feet on the peasant Lalli. A sculpture on wood illustrates the same subject in the north aisle.