Christina of Denmark was a Danish princess, the younger surviving daughter of King Christian II of Denmark and Norway and Isabella of Austria. By her two marriages, she became Duchess of Milan, then Duchess of Lorraine. She served as the regent of Lorraine from 1545 to 1552 during the minority of her son. She was also a claimant to the thrones of Denmark, Norway and Sweden in 1561–1590 and was sovereign Lady of Tortona in 1578–1584.

Christian II was a Scandinavian monarch under the Kalmar Union who reigned as King of Denmark and Norway, from 1513 until 1523, and Sweden from 1520 until 1521. From 1513 to 1523, he was concurrently Duke of Schleswig and Holstein in joint rule with his uncle Frederick.