Frederick I, Elector of Brandenburg

Frederick I (1371–1440) was a Hohenzollern prince who ruled Nuremberg as Burgrave Frederick VI. A trusted servant of King Sigismund, he fought at Nicopolis in 1396 and represented him in the disputed 1410 imperial election. In 1411 Sigismund made him administrator of Brandenburg, where he crushed the rebellious nobility. At the Council of Constance in 1415 Sigismund made him Margrave and Elector of Brandenburg, with formal enfeoffment in 1417, founding Hohenzollern rule there.

Frederick withdrew to Cadolzburg in 1425 and transferred the regency of Brandenburg to his son John in 1426, remaining elector until his death in 1440.