Birger Jarl
Valdemar was the son of the Swedish princess Ingeborg Eriksdotter and Birger Jarl, from the House of Bjelbo. When her brother King Eric XI died in 1250, though a child, Valdemar was elected king and crowned the following year in the cathedral at Linköping. During the first sixteen years of his reign, it was Birger Jarl who was the real ruler. Birger Jarl had been the de facto ruler of Sweden from 1248, before the reign of Valdemar, even under Eric XI. Valdemar's mother and King Eric were children of King Eric X and Richeza of Denmark.