John
margrave of Brandenburg
John (born Aug. 3, 1513, Tangermünde, Brandenburg—died Jan. 13, 1571, Küstrin, Neumark, Brandenburg) was the margrave of Brandenburg-Küstrin and a German Protestant ruler who remained loyal to the Catholic Habsburg emperors; he fought against his fellow Protestant princes and was conspicuously successful in the government of his territories. John was the younger son of Joachim I, elector of Brandenburg, who divided his territory between his two sons. John inherited the eastern lands, the so-called Neumark,...