Sweden and Denmark have been in a state of war against each other from 1451.

A growing opposition against Charles VIII Knutsson has emerged in Sweden because of the devastating conflict.

The Swedish church, which opposes Charles's efforts to concentrate royal and secular power, is his strongest opponent.

Other opponents include the family group of Oxenstierna and Vasa (House), which had been in the opposing side in the election of the king in 1449 and lost.

A rebellion led by Jöns Bengtsson (Oxenstierna), Archbishop of Sweden, and a nobleman, Erik Axelsson Tott, in 1457 deposes Charles, who goes into exile to Danzig (Gdańsk).

The two leaders of the revolt name themselves co-regents, and organize the election of Christian I of Denmark and Norway as king of Sweden (firstly in Turku, later in Stockholm), thus reestablishing the Kalmar Union.