Christian III of Denmark

Christian III took the Danish throne in 1534 after a contested succession, then absorbed Norway's crown three years later in 1537. He used that consolidated power to enforce the Protestant Reformation from above, establishing Lutheranism as the official state religion across both kingdoms. The move bound the church tightly to royal authority and made him the first king to rule a unified Denmark-Norway. He held that double crown until his death on New Year's Day 1559, leaving behind a religious settlement that defined Scandinavian identity for generations.