Harald Hen was King of Denmark from 1076 to 1080. Harald III was an illegitimate son of Danish king Sweyn II Estridsson, and contested the crown with some of his brothers. He was a peaceful ruler who initiated a number of reforms. Harald was married to his cousin Margareta Hasbjörnsdatter, but did not leave any heirs, and was succeeded by his brother Canute IV the Saint. Four of his half-brothers were in turn crowned Danish kings.

Sweyn Estridsson Ulfsson was King of Denmark from 1047 until his death in 1076. He was the son of Ulf Thorgilsson and Estrid Svendsdatter, and the grandson of Sweyn Forkbeard through his mother's line. He was married at least two times, and fathered 20 children or more out of wedlock, including the five future kings Harald Hen, Canute the Saint, Oluf Hunger, Eric Evergood, and Niels.