John Casimir of Saxe-Coburg (Gotha, 12 June 1564 – Coburg, 16 July 1633) was the Duke of Saxe-Coburg. He was the descendant of the Ernestine branch of the House of Wettin. Under his rule, the residence town of Coburg prospered with many Renaissance buildings being erected that still remain today. Youth John Casimir was born at Grimmenstein Castle in Gotha on 12 June 1564 as the middle of three sons of Duke John Frederick II, Duke of Saxony and his wife Countess Palatine Elisabeth of Simmern-Sponheim. Because of the Holy Roman Empire's sanctions (Reichsexekution) against Gotha, his father lost on 15 April 1567 his dominions and freedom. Then John Casimir lived with his brothers, Frederick Henry (who died in 1572 at the age of 11) and John Ernest and their mother, first in Eisenach, then at the court of his Uncle John William, the guardian of the children, in Weimar, and finally in Eisenberg, Thuringia. In 1570 the Diet of Speyer restored to the brothers the rights and privileges of their father. Two years later, in the summer of 1572, their mother moved to Austria to join her husband in captivity. A few months later, on 6 November 1572, her two sons were awarded by the Division of Erfurt the Principality of Saxe-Coburg-Eisenach. The Principality consisted of southern and western areas of Thuringia, including the cities of Eisenach, Gotha and Hildburghausen. The additional guardians of the children were John George, Elector of Brandenburg (since 1578 Margrave George Frederick of Brandenburg-Anspach) and the material grandfather, Frederick III, Elector of the Palatinate, and also the enemy of his father, Augustus, Elector of Saxony, who supervised the education of John Casimir as well as the regency of the new Principality in Coburg. John Casimir and his brother moved to Coburg on 5 December 1572. His guardians undersigned in the name of John Casimir the Formula of Concord (Konkordienformel) of 1577 and the Book of Concord (Konkordienbuch) of 1580, the two authoritative statements of the Lutheran faith. Between 1578 and 1581 Johann Casimir studied at the University of Leipzig. On 6 May 1584 he became engaged, without the consent of his father, with Anna, the daughter of Augustus of Saxony, whom he married on 16 January 1586 in Dresden. Only after the death of the Elector Augustus of Saxony on 11 February 1586 was Duke John Casimir at the age of 22 years able