Frederick was the younger son of the first Oldenburg King Christian I of Denmark, Norway and Sweden and of Dorothea of Brandenburg. Soon after the death of his father, the underage Frederick was elected co-Duke of Schleswig and Holstein in 1482, the other co-duke being his elder brother, King John of Denmark. In 1490 at Frederick's majority, both duchies were divided between the brothers. In 1500 he had convinced his brother King John to conquer Dithmarschen. A great army was called from not only the duchies, but with additions from all of the Kalmar Union for which his brother briefly was king. In addition, numerous German mercenaries took part. The expedition failed miserably, however, in the Battle of Hemmingstedt, where one third of all knights of Schleswig and Holstein lost their lives.
Reign
When his brother, King John died, a group of Jutish nobles had offered Frederick the throne as early as 1513, but he had declined, rightly believing that the majority of the Danish nobility would be loyal to his nephew Christian II. In 1523, Christian was forced by disloyal nobles to abdicate, and Frederick took the throne. It is not certain that Frederick ever learned to speak Danish. After becoming king, he continued spending most of his time at Gottorp, a castle and estate in the city of Schleswig. In 1524 and 1525 Frederick had to suppress revolts among the peasants in Agder, Jutland and Scania who demanded the restoration of Christian II. The high point of the rebellion came in 1525 when Søren Norby, the governor of Gotland, invaded Blekinge in an attempt to restore Christian II to power. He raised 8000 men who besieged Kärnan, a castle in Helsingborg. Frederick's general, Johann Rantzau, moved his army to Scania and defeated the peasants soundly in April and May 1525. Frederick played a central role in the spread of Lutheran teaching throughout Denmark. In his coronation charter, he was made the solemn protector of Roman Catholicism in Denmark. In that role, he asserted his right to select bishops for the Roman Catholic dioceses in the country. Christian II had been intolerant of Protestant teaching, but Frederick took a more opportunist approach. For example, he ordered that Lutherans and Roman Catholics share the same churches and encouraged the first publication of the Bible in the Danish language. In 1526, when Lutheran Reformer Hans Tausen was threatened with arrest and trial for heresy, Frederick appointed him his personal chaplain to give him immunity. Starting in 1527, Frederick authorized the closure of Franciscan houses and monasteries in 28 Danish cities. He used the popular anti-establishment feelings that ran against some persons of the Roman Catholic hierarchy and nobility of Denmark as well as keen propaganda to decrease the power of bishops and Roman Catholic nobles. During his reign, Frederick was skillful enough to prevent all-out warfare between Protestants and Roman Catholics. In 1532 he succeeded in capturing Christian II who had tried to make a political come-back in Norway. Frederick died on 10 April 1533 in Gottorp, at the age of 61, and was buried in Schleswig Cathedral. Upon Frederick's death, tensions between Roman Catholics and Protestants rose to a fever pitch which would result in the Count's Feud.
