The Lutheran party objected strongly to this decree, and as their
objections were over-ruled they submitted a formal protest, on account
of which they received the distinctive title of Protestants.[28] The
protest, signed by the Elector of Saxony, the Margrave of Brandenburg,
the Dukes of Brunswick-Luneburg, Philip of Hesse, and the
representatives of fourteen cities, having failed to produce any
effect on the Diet, a deputation was appointed to interview the
Emperor and to place their grievances before him. But Charles V.,
mindful of his imperial oath, refused to allow himself to be
intimidated. He warned the deputation that he and the Catholic princes
had also their duties to fulfil towards God and the Church, and that
until a Council should assemble they must obey the decrees of the
Diet. In January 1530 he convened a new Diet to meet at Augsburg at
which he himself promised to be present.

The Diet was convened to meet at Augsburg in April 1530, but it was
the middle of June before the Emperor, accompanied by the papal
legate, made his formal entrance into the city. On the following day
the feast of Corpus Christi was celebrated with the customary
solemnities, and the Emperor was pained deeply when he learned that
the Protestant princes refused to be present or to take any part in
the function. At the opening of the Diet it was agreed that the
religious question should take precedence, and the Protestant princes
were invited to make a clear statement of their doctrines and demands.
Luther himself could not be present on account of the decree of Worms,
and hence the duty of preparing a complete exposition of the
Protestant doctrine devolved upon the ablest of his lieutenants,
Philip Melanchthon. He drew up and presented to the Diet the document
known as the /Augsburg Confession/ (/Confessio Augustana/), accepted
by Luther himself as a masterly though perhaps too moderate statement