Was the Diet of Spires held under Catholic or Protestant auspices?

The Catholic Answers

Under Catholic auspices. It was convened by Charles V., a Catholic sovereign, chiefly to secure temporal peace. In 1517 Luther had broken into open revolt against the Catholic Church, preaching new and heretical doctrines. Charles V. became Emperor in 1520. Many German states, anxious to revolt politically against Charles, followed the new religious revolt of Luther. Chaos reigned in Germany. The Emperor was anxious for political peace; the Pope was anxious to stop the corruption of Catholicism by the preaching of these new doctrines. Charles, therefore, called a Diet or general assembly of all the lesser German princes at Spires in 1529. Pope Clement VII. urged Charles to take up the cause of the Catholic religion at the same time, and in reference to religion, the Diet made three main propositions. The celebration of Mass was to be permitted in those states where Protestants had forbidden it. The reformers were to be free to practice their new religion in those states where it had already been accepted, but it was not to be propagated beyond those states. No sect which denied the Real Presence of Christ in the Eucharist could be tolerated. The vast majority of Protestants at the Diet approved these laws, but the evangelical minority, whilst accepting the third law, refused to permit Mass, and to refrain from preaching Protestantism to still Catholic peoples. They formally protested that the religion of the people in a given place must be the religion of the temporal ruler of the country, and it is from this protest at the Diet of Spires in 1529 that the word Protestant is derived. It was a protest against freedom of conscience, and against the spiritual authority of the Catholic Church, as well as against the temporal authority of Charles V.

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