King Cnut (Canute) - byname Canute the Great (d. Nov 12, 1035). Place and date of birth unknown. Danish king: of England (1016-1035); of Denmark (as Canute I, 1019-1035); of Norway (1028-1035).
Harald III Sigurdsson - byname Harald Hardrada (various spellings) b. 1015, Norway - d. Sep 25, 1066 at Battle of Stamford Bridge, Yorkshire, England. King of Norway (1045-1066). Harald's half brother (by his mother, Estrid) was Norwegian king Olaf II Haraldsson (St. Olaf).
Connection: Canute fomented with bribes the unrest of landowners againgst king Olaf II and was able to drive him out in 1028. In 1030, Olaf II tried to return to the thrown and fought with Harald Hardrada (15 yrs old) at the celebrated batlle of Stiklestad in which Olaf II died. Harald Hardrad fled to Russia and did not return to Norway until 1045.
Source: The New Encyclopaedia Britannica