North Sea Empire

State · 1018–1039 CE · at its largest around 1028 CE

Personal union of England, Denmark and Norway under the Danish king Cnut the Great, which broke apart soon after his death in 1035.

On its lands while it lasted

• Cnut the Great (c. 990 CE – 1035 CE): Danish prince who became king of England, Denmark and Norway, ruling a North Sea empire.
• Gniezno (c. 1025 CE): Capital of Kingdom of Poland (1025–1385).
• Battle of Stiklestad (1030 CE): King Olaf II of Norway was killed fighting his rebellious subjects; he was soon venerated as Saint Olaf, patron saint of Norway.

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