Christian III (12 August 1503 – 1 January 1559) reigned as King of Denmark from 1534 until his death, and King of Norway from 1537 until his death. During his reign, Christian established Lutheranism as the state religion within his realms as part of the Protestant Reformation. Christian was the eldest son of future king, Frederick I of Denmark, and Anna of Brandenburg. He was born at Gottorf Castle in Schleswig which Frederick I had made as a primary residence. In 1514, when he was just ten years old, Christian's mother died. Four years later, his father remarried to Sophie of Pomerania (1498–1568). In 1523, Frederick I was elected King of Denmark in the place of his nephew, King Christian II of Denmark. The young Prince Christian's first public service after his father became king was gaining the submission of Copenhagen, which stood firm for the fugitive, King Christian II. As stadtholder of the Duchies of Holstein and Schleswig in 1526, and as viceroy of Norway in 1529, Christian III displayed considerable administrative ability. After his father's death, in 1533, Christian was proclaimed king at an assembly in Rye, a town in eastern Jutland, in 1534. The Danish State Council (rigsraad), dominated by Roman Catholic bishops and nobles, refused to accept Duke Christian as king and turned to Count Christopher of Oldenburg (c. 1504–1566) in order to restore Christian II to the Danish throne. Christian II had supported both the Roman Catholics and Protestant Reformers at various times. In opposition to King Christian III, Count Christopher was proclaimed regent. This resulted in a two-year civil war, known as the Count's Feud (Grevens Fejde, 1534–36), between Protestant and Catholic forces. Count Christopher's forces held out in Malmø and Copenhagen until July 1536 when they surrendered after several months of siege by Christian III's forces. With their capitulation, Christian III was firmly placed upon Denmark's throne, and the Roman Catholic forces in Denmark were subdued. A mutual confidence between a king who had conquered his kingdom and a people who had stood in arms against him was not attainable immediately. The circumstances under which Christian III ascended the throne exposed Denmark to the danger of foreign domination.

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