After the death of Luther in 1545 Melanchthon became the acknowledged head of the Lutheran party. On many questions he was inclined to disagree with the doctrine of his master. His teaching in regard to the Eucharist began to approximate more closely to the views of Calvin, so that the Impanation and Companation theories of Luther lost favour in Germany. The Philippists or Crypto-Calvinists gained ground rapidly in the country, with the result that the German Protestants were split up into hostile sections. A conference was held at Naumburg in 1561, but it broke up without having done anything to restore religious unity. At last in 1576 the Elector August of Saxony summoned an assembly of theologians to meet at Torgau, for the discussion of the differences that had arisen between the orthodox followers of Luther and the Crypto-Calvinists or followers of Melanchthon. Jacob Andrea, chancellor of the University of Tubingen, was the life and soul of the reunion movement. Taking the plan of agreement that had been formulated by him as a basis for discussion the conference drew up the /Book of Torgau/, copies of which were despatched to the Lutheran princes and theologians for an expression of their opinion. When this had been received the /Book of Torgau/ was revised (1577) and a Formula of Concord (/Formula Concordiae/) was compiled, embodying the Confession of Augsburg, Melanchthon's Apology for this Confession, the Articles of Schmalkald and the two Catechisms issued by Luther (1577). But as there was no authority to enforce this Formula several of the states refused to accept it. In Saxony under Christian I. (1586-91) the Philippists in favour at court triumphed over their adversaries, but on the death of Christian the orthodox Lutherans secured the upper hand, and Nicholas Crell, the prime minister and chancellor of Saxony during the previous reign, was thrown into prison, and later on he was put to death (1601). Calvinism continued to make steady progress in Germany. It was introduced into the Palatinate during the reign of Frederick III. (1583), and though suppressed by his son and successor, it gained the upper hand. Similarly in Hesse-Cassel, in Lippe, Brandenburg, and Anhalt, it gained many new adherents. All attempts at peace amongst the warring sects having failed, Calvinism was recognised formally at the Peace of Westphalia (1648).