Olaf IV of Norway

Olaf IV Haakonsson, (1370 - August 23, 1387), King of Norway and Denmark, son of Haakon VI of Norway and Margaret of Denmark. Haakon was son of King Magnus II of Sweden and Margaret daughter of King Waldemar Atterdag of Denmark.

Olaf inherited the Danish throne through his mother and reigned as king of Denmark (1376-1387) as Oluf III and the Norwegian throne from his father and reigned in Norway (1380-1387) as Olav IV. Following his premature death in 1387 his mother Margaren, was by the Kalmar Union in 1389, able to unite, in personal union, the three Scandinavian kingdoms under one crown.