John_Frederick_III,_Duke_of_Saxony
Johann Frederick III, also known as Johann Frederick the Younger (16 January 1538 in Torgau – 21 October 1565 in Jena) was German nobleman. He was a titular Duke of Saxony from the Ernestine branch of the House of Wettin. He received Saxe-Gotha as an apanage, but left its administration to his eldest brother.