The new phase saw the German war expanded into an international conflict. Christian IV of Denmark came into the fighting, principally because of his fear of the rise of Hapsburg power in N Germany; he openly avowed religious motives but hoped also to enlarge his German possessions. England and the United Provinces gave a subsidy to aid the opponents of the Hapsburgs, and England sent a few thousand soldiers. Christian IV advanced into Germany. The emperor's cause was advanced by the work of Wallenstein, who gathered an effective army and defeated Mansfeld at Dessau (1626). A little later the Danish king was soundly defeated by Tilly at Lutter.
The imperial armies swept through most of Germany. Wallenstein went into Jutland and vanquished the Danes but failed before Stralsund (1628). In 1629, Denmark, by the Treaty of Lübeck, withdrew from the war and surrendered the N German bishoprics. The Edict of Restitution (1629), issued by Ferdinand II, attempted to enforce the ecclesiastical reservation of the Peace of Augsburg and declared void Protestant titles to lands secularized after 1552; its full application would have had a disastrous effect on German Protestantism and naturally aroused the Protestant states to determined, if at first latent, hostility.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.