"Christian II (1 July 1481 – 25 January 1559) was a Scandinavian monarch under the Kalmar Union. He reigned as King of Denmark and Norway from 1513 until 1523 and of Sweden from 1520 until 1521. From 1513 to 1523, he was concurrently Duke of Schleswig and Holstein in joint rule with his uncle Frederick.
Christian was the oldest son of King John and belonged to the House of Oldenburg. Denmark was then an elective monarchy in which the nobility elected the new king (from among the sons or close male relatives of the previous monarch), who had to share his power with them. He came into conflict with the Danish nobility when he was forced to sign a charter, more strict than any previous, to ensure his access to the throne. Through domestic reforms he later sought to evade the restrictions of the charter." - (en.wikipedia.org 17.11.2019)
)
