The Historia Norwegie names "Haroldum Grensca" as son of "Gudrodus", commenting that he acquired his nickname from having been brought up "in Grenlandia". Snorre names Harald as son of Gudröd & his wife, recording that, after his father's death, he fled to the Uplands and from there eastwards into Svithjod. He supported the invasion of Norway by Harald King of Denmark in 965, and was rewarded with Vingulmark, Vestfold and Agder with the title of king.
He was murdered on the orders of Sigrid "Storrada/the Haughty", widow of Erik King of Sweden, to whom Harald "Grenske" proposed marriage (despite already being married to Asta). 1
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