John, born at Aalborghus, in Aalborg, to Christian I of Denmark and Dorothea of Brandenburg, daughter of Margrave John of Brandenburg, had in 1478 married Christina of Saxony, granddaughter of Frederick the Gentle of Saxony.

This produced the following offspring: Christian II, Francis, Knud, and Elisabeth, who later married as princess of Brandenburg.

In 1458, John's father, King Christian I, had had the Norwegian Council of the Realm commit to electing Christian's eldest son as next king of Norway upon his death.

A similar declaration had been made in Sweden.

In 1467, John had been hailed as successor to the throne in Denmark.

John uses the title heir to the throne of Norway, in line with Norway's old status as a hereditary kingdom, but this is a claim the Norwegian Council had not immediately recognized.

Consequently, upon King Christian's death in May 1481, John's position is unchallenged in Denmark, whereas …