te: October 1546]

In the meantime Duke Maurice of Albertine Saxony, having made a bargain
with the emperor, attacked his second cousin the Elector. Though
Maurice was not obliged to abjure his faith, his act was naturally
regarded as one of signal treachery and he was henceforth known by the
nickname "Judas." Maurice conquered most of his cousin's lands, except
the forts of Wittenberg and Gotha. Charles's Spanish army under Alva
now turned northward, forced a passage of the Elbe and routed the
troops of John Frederic at the battle of Muelberg, near Torgau, on April
24, 1547. John Frederic was captured wounded, and kept in durance
several years. Wittenberg capitulated on May 19, and just a month
later Philip of Hesse surrendered at Halle. He also was kept a
prisoner for some years. Peace was made by the mediation of
Brandenburg. The electoral vote of Saxony was given to Maurice, and
with it the best part of John Frederic's lands, including Wittenberg.
No change of religion was required. The net result of the war was to
{129} increase the imperial power, but to put a very slight check upon
the expansion of Protestantism.

And yet it was for precisely this end that Charles chiefly valued his
authority. Immediately, acting independently of the pope, he made
another effort to restore the confessional unity of Germany. The Diet
of Augsburg [Sidenote: 1547-8] accepted under pressure from him a
decree called the Interim because it was to be valid only until the
final decisions of a general council. Though intended to apply only to
Protestant states--the Catholics had, instead, a _formula
reformationis_--the Interim [Sidenote: The Interim, June 30, 1548],
drawn up by Romanist divines, was naturally Catholic in tenor. The
episcopal constitution was restored, along with the canon of the mass,
the doctrine of the seven sacraments, and the worship of saints. On
some doctrinal points vagueness was studied. The only concessions made
to the Reformation were the _pro tempore_ recognition of the marriage
of the clergy and the giving of the cup to the laity. Various other
details of practical reform were demanded. The Interim was intensely
unpopular with both parties. The pope objected to it and German
Catholics, especially in Bavaria, strongly opposed it. The South
German Protestant states accepted it only under pressure. Maurice of
Saxony adopted it in a modified form, known as the Leipzig Interim, in
December 154