Gustavus Vasa was a Swedish king who reigned from 1523 to 1560. He is known for leading the Swedish War of Liberation against the Danish and establishing Sweden as an independent and unified kingdom. Gustavus Vasa is also credited with introducing Protestantism to Sweden and implementing various reforms to strengthen the country's economy and government. His reign is considered a pivotal period in Swedish history, marking the transition from the Kalmar Union to the rise of the Swedish Empire.