646 Outliiies of Einvpean History Section 113. The Thirty Years' War The Thirty Years' War really a series of wars Weaknesses of the Peace of Augsburg Spread of Protestant- Opening of the Thirty Years' War, 1618 The last great conflict caused by the differences between the Catholics and Protestants was fought out in Germany during the first half of the seventeenth century. It is generally known as the Thirty Years' War (16 18-1648), but there was in reality a series of wars ; and although the fighting was done upon German territory, Sweden, France, and Spain played quite as important a part in the struggle as the various German states. Just before the abdication of Charles V, the Lutheran princes had forced the Emperor to acknowledge their right to their own religion and to the church property which they had appropriated. The religious Peace of Augsburg had, however, as we have seen,^ two great weaknesses. In the first place only those Protestants who held the Lutheran faith were to be tolerated. The Calvinists, who were increasing in numbers, were not in- cluded in the peace. In the second place the peace did not put a stop to the seizure of church property by the Protestant princes. Protestantism, however, made rapid progress and invaded the Austrian possessions and, above all, Bohemia. So it looked for a time as if even the Catholic Hapsburgs were to see large por- tions of their territory falling away from the old Church. But the Catholics had in the Jesuits a band of active and efficient missionaries. They not only preached and founded schools, but also succeeded in gaining the confidence of some of the German princes, whose chief advisers they became. Conditions were very favorable, at the opening of the seventeenth century, for a renewal of the religious struggle. The long war began in Bohemia in 161 8. This portion of the Austrian possessions was strongly Protestant and decided that the best policy was to declare its independence of the Haps- burgs and set up a king of its own. It chose Frederick, the Elector of the Palatinate, a Calvinist who would, it was hoped, 1 See above, p. 603.