Scandinavia looms large in the Middle Ages as the home of the teeming multitudes of emigrants, Goths and Vandals, who swarmed over the Roman Empire. Later waves from Denmark and the contiguous portion of Germany flooded England first in the Anglo-Saxon conquest and then in the Danish. The Normans, too, originally hailed from Scandinavia. But though the sons of the North conquered and colonized so much of the South, Scandinavia herself remained a small people, neither politically nor intellectually of the first importance. The three kingdoms of Denmark, Norway, and Sweden became one in 1397; and, after Sweden's temporary separation from the other two, were again united. The fifteenth century saw the {136} great aggrandizement of the power of the prelates and of the larger nobles at the expense of the _boender_, who, from a class of free and noble small proprietors degenerated not only into peasants but often into serfs. [Sidenote: 1513] When Christian II succeeded to the throne, it was as the papal champion. His attempt to consolidate his power in Sweden by massacring the magnates under the pretext that they were hostile to the pope, [Sidenote: November 8-11, 1520] an act called the "Stockholm bath of blood," aroused the people against him in a war of independence. [Sidenote: Denmark] Christian found Denmark also insubordinate. It is true that he made some just laws, protecting the people and building up their prosperity, but their support was insufficient to counterbalance the hatred of the great lords spiritual and temporal. He was quick to see in the Reformation a weapon against the prelates, and appealed for help to Wittenberg as early as 1519. His endeavors throughout 1520 to get Luther himself to visit Denmark failed, but early in 1521 he succeeded in attracting Carlstadt for a short visit. This effort, however, cost him his throne, for he was expelled on April 13, 1523, and wandered over Europe in exile until his death. [Sidenote: 1559] The Duke of Schleswig-Holstein, to whom the crown was offered, reigned for ten years as Frederic I. Though his coronation oath bound him to do nothing against the church, he had only been king for three years before he came out openly for the Reformation. In this again we must see primarily a policy, rather than a conviction. He was supported, however, by the common people, who had been disgusted by the indulgences sold by Arcimboldi [Sidenote: 1516-19] and by the constant corruption of the higher clergy. The cities, as in Germany, were the strongest centers of the movement. The Diet of 1527 decreed that Lutherans should be recognized on equal terms with Catholics, that marriage of priests {137} and the regular clergy be allowed. In 1530 a Lutheran confession was adopted.