Most German Protestants became Lutherans because of the influence of Martin Luther in his own country. However, the intolerance of the strict Lutheran party against the Calvinists and the moderate Lutherans (called, after their leader, Melanchthonians or Philippists) drove a large number of the latter over to the Reformed (Calvinistic) Church, especially in the Palatinate (1560), in Bremen (1561), Nassau (1582), Anhalt (1596), Hesse-Cassel (1605), and Brandenburg (1614). The German Reformed communion adopted the Heidelberg Catechism -- drawn up by two moderate Calvinistic divines, Zacharias Ursinus and Kaspar Olevianus, in 1563, by order of the elector Frederick III., or the Pious -- as their confession of faith.