answered this in a tract of the utmost violence, called _Jack Sausage_.
Henry's rejoinder was followed by war between him and the Schmalkaldic
princes, in which he was expelled from his dominions and the
Reformation introduced.

[Sidenote: 1541]

Further gains followed rapidly. The Catholic Bishop of Naumburg was
expelled by John Frederic of Saxony, and a Lutheran bishop instituted
instead. About the same time the great spiritual prince, Hermann von
Wied, Archbishop Elector of Cologne, became a Protestant, and invited
Melanchthon and Bucer to reform his territories. One of the last
gains, before the Schmalkaldic war, was the Rhenish Palatinate, under
{121} its Elector Frederic III. [Sidenote: 1545] His troops fought
then on the Protestant side, though later he turned against that church.

The opportunity of the Lutherans was due to the engagements of the
emperor with other enemies. In 1535 Charles undertook a successful
expedition against Tunis. The war with France simmered on until the
Truce of Nice, intended to be for ten years, signed between the two
powers in 1538. In 1544 war broke out again, and fortune again favored
Charles. He invaded France almost to the gates of Paris, but did not
press his advantage and on September 18 signed the Peace of Crepy
giving up all his conquests.

Unable to turn his arms against the heretics, Charles continued to
negotiate with them. The pressure he brought to bear upon the pope
finally resulted in the summoning by Paul III of a council to meet at
Mantua the following year. [Sidenote: June 2, 1536] The Protestants
were invited to send delegates to this council, and the princes of that
faith held a congress at Schmalkalden to decide on their course.
[Sidenote: February 1537] Hitherto the Lutherans had called themselves
a part of the Roman Catholic church and had always appealed to a future
oecumenical or national synod. They now found this position untenable,
and returned the papal citation unopened. Instead, demands for reform,
known as the Schmalkaldic Articles, were drawn up by Luther. The four
principal demands were (1) recognition of the doctrine of justification
by faith only, (2) abolition of the mass as a good work or _opus
operatum_, (3) alienation of the foundations for private masses, (4)
removal of the pretentions of the pope to headship of the universal
church. As a matter of fact the council was postponed.

[Sidenote: April 19, 1539]

Failing to