FREDERICK I. surnamed "the Warlike," elector and duke of Saxony, was the eldest son of Frederick "the Stern," count of Osterland, and Catherine, daughter and heiress of Henry VIII., count of Coburg. He was born at Altenburg on April i 1, 1370, and was a member of the family of Wettin. In the division of their father's lands in 1382 Frederick and his brothers shared Meissen and Thuringia with their uncles Balthasar and William. Frederick's brother George died in 1402, and his uncle William in 1407. A further dispute then arose, but in 1410 a treaty was made at Naumburg, when Frederick and his brother William added the northern part of Meissen to their lands; and in 1425 the death of William left Frederick sole ruler. In the German town war of 1388 he assisted Frederick V. of Hohen zollern, burgrave of Nuremberg, and in 1391 did the same for the Teutonic Order against Ladislaus V., king of Poland and prince of Lithuania. He supported Rupert III., elector palatine of the Rhine, in his struggle with King Wenceslaus for the German throne, probably because Wenceslaus refused to fulfil a promise to give him his sister Anna in marriage. He took a leading part in the war against the Hussites, receiving from the German King Sigismund, as a return for his services, various places in Bohemia and elsewhere in pledge, together with the vacant electoral duchy of Saxe-Wittenberg. He was formally invested at Budapest on Aug. 1, 1425. The elector was endeavouring to rouse the German princes to aid him in prosecuting the war against the Hussites when the Saxon army was almost annihilated at Aussig (1426). Frederick died at Altenburg on Jan. 4, 1428. In 1402 he married Catherine of Brunswick, by whom he left four sons and two daughters. He and his brother William founded the university of Leipzig for German students who had just left the university of Prague. Frederick's importance as an historical figure arises from his having obtained the electorate of Saxe-Wittenberg for the house of Wettin, and transformed the margraviate of Meissen into the territory which afterwards became the kingdom of Sax ony. The ex-king of Saxony, the sovereigns of England and of the Belgians are his direct descendants.