Gustavus I Eriksson (1496-1560), first king of modern Sweden, reigned from 1523 to 1560. He led Sweden from chaos to a position as a minor European power.

Gustavus Vasa was born at his mother's estate at Lindholm on Ascension Day, 1496. The Vasas had played an active role in Swedish politics during the 15th century, but usually in the Union party rather than the Nationalist. His father, however, was in the party of Sten Sture, Regent of Sweden, who led the peasantry and some nobles against the Danish Union. In 1516 Gustavus was sent to Denmark as a hostage and was imprisoned in the island fortress of Kalö. He escaped to Lübeck in September 1519 and returned as a fugitive in May 1520 to Kalmar in Sweden.

In January of that year Sten Sture had died and left the forces of the Swedish peasantry leaderless. In March, Christian II had been...