[2] During the reign of his elder brother Canute IV, Olaf supposedly served as Duke of Schleswig.

Canute was held up and could not join the leding, and as the navy grew weary in waiting for him, Olaf became the spokesperson for its concerns.

According to Arild Hvitfeldt's "Danmarks Riges Krønike", in those years springtime was so dry that the fields looked as if they had been burned, and in the fall the skies opened up and rain fell so often that people floated about on pieces of wood to cut the heads off the grain that rose above the water.

[2] Chronicler Saxo Grammaticus described the hunger as a strictly Danish phenomenon, though it has later been described as a general problem of Europe in those years.

[2][3] Oluf probably cut the Danish ties to the Papal Gregorian reform movement, supporting Antipope Wibert of Ravenna instead.

[3] During Olaf's reign, some of Canute's laws were repealed, and the power of the clergy and royalty receded in favour of the magnates.

Saxo Grammaticus writes that he "willingly gave himself to lose the land of its bad luck and begged that all of it (guilt) would fall upon his head alone.