Excerpts from Books and Wikipedia
"Cnut the Great (...), also known as Canute, was King of England, Denmark and Norway, often referred to together as the North Sea Empire during his rule. . . . Dominion of England lent the Danes an important link to the maritime zone between the islands of Great Britain and Ireland, where Cnut, like his father before him, had a strong interest and wielded much influence among the Norse–Gaels. Cnut's possession of England's dioceses and the continental Diocese of Denmark—with a claim laid upon it by the Holy Roman Empire's Archdiocese of Hamburg-Bremen—was a source of great prestige and leverage within the Catholic Church . . ." [Wikipedia] "Danes become kings of England for the next 26 years before the last rise of the Anglo-Saxons before the Norman Conquest." [Wikipedia: Timeline of Middle Ages]