Margaret of Denmark (1353-1412) was a fourteenth-century Danish queen and first medieval queen to rule in Europe, who united three powerful Scandinavian kingdoms.

In the 11th century, the kingdoms of Scandinavia were a relatively new feature of medieval Europe . During the earliest phase of Viking attacks on Europe, the area was characterized by disunity; bands of Vikings from various Scandinavian areas looted Western Europe for personal or regional gain. But from the late ninth through the 11th centuries, the Scandinavian rulers had consolidated the area; by 1100 three distinct kingdoms--Norway, Sweden, and Denmark--had been created. By this time, there were significant regional differences in language and in rules of royal succession which ensured the separate development of the kingdoms. Of these northern realms, only Iceland existed without a king; by the mid-13th century, however, the king of Norway claimed jurisdiction there. Notwithstanding the 11th-century achievements of King Canute...