Sten Sture the Elder (Swedish: Sten Sture den äldre; 1440 – 14 December 1503) was a Swedish statesman and regent of Sweden from 1470 to 1497 and again from 1501 to 1503. As the leader of the victorious Swedish separatist forces against the royal unionist forces led by Danish king Christian I during the Battle of Brunkeberg in 1471, he weakened the Kalmar Union considerably and became the effective ruler of Sweden as Lord Regent for most of his remaining life.
Christian I (Christiern I) (February 1426 – 21 May 1481) was a German noble and Scandinavian monarch under the Kalmar Union. He was king of Denmark (1448–1481), Norway (1450–1481) and Sweden (1457–1464). From 1460 to 1481, he was also duke of Schleswig (within Denmark) and count (after 1474, duke) of Holstein (within the Holy Roman Empire). He was the first king of the House of Oldenburg.
In the power vacuum that arose following the death of King Christopher without a direct heir in 1448, Sweden elected Karl Knutsson king with the intent to reestablish the union under a Swedish king. Karl was elected king of Norway in the following year. However the counts of Holstein made the Danish Privy Council appoint Christian as king of Denmark. His subsequent accessions to the thrones of Norway (in 1450) and Sweden (in 1457) restored the unity of the Kalmar Union for a short period. In 1464, Sweden broke away from the union and Christian's attempt at a reconquest resulted in his defeat by the Swedish regent Sten Sture the Elder at the Battle of Brunkeberg in 1471.
The Battle of Brunkeberg was fought on 10 October 1471 between the Swedish regent Sten Sture the Elder and forces led by Danish king Christian I. Sture won a decisive victory, weakening the Kalmar Union considerably and becoming the effective ruler of Sweden as Lord Regent for most of his remaining life.