Dorothea of Denmark (1520-1571) was a Danish princess, the daughter of King Christian II of Denmark and Isabella of Austria. She became the Duchess of Sleswig through her marriage to Franz I, Duke of Sleswig. Dorothea played a significant role in the political landscape of her time, particularly in the context of the Reformation and the shifting alliances in Northern Europe. Throughout her life, Dorothea was known for her strong character and influence. After her husband's death, she took on a more active role in governance, managing the duchy and supporting her children. Her legacy includes her contributions to the cultural and political life of Denmark and Sleswig.