Diet of Ratisbon (1541)

The Colloquy of Regensburg, historically called the Colloquy of Ratisbon, was a conference held at Regensburg (Ratisbon) in 1541, during the Protestant Reformation, which marks the culmination of attempts to restore religious unity in the Holy Roman Empire by means of theological debate between the Protestants and the Catholics.

Delegates from the various factions had met at Haguenau in 1540 and at Worms in January 1541 but the latter session of the Imperial Diet was adjourned by the Emperor Charles V as the Diet was preparing to meet at Regensburg. The subject for debate was to be the Augsburg Confession, the primary doctrinal statement of the Protestant movement, and the Apology of the Augsburg Confession, a defence of the Confession written by Philipp Melancthon.

On 15 December 1540 a secret conference took place between Johann Gropper, canon of Cologne, and Gerhard Veltwick, the Imperial secretary, on the one side and Butzer and Capito, the delegates of Protestant Strasbourg, on the other. The two sides agreed their positions on original sin and justification, but the promise made by the Catholic party at Haguenau, to negotiate on the basis of the Confession and Apology, was withdrawn.

Early in 1541, Butzer sent a draft of the conclusions to Joachim II, Elector of Brandenburg, with the request to communicate it to Luther and the other princes of the Protestant league. The document was essentially identical with the later so-called Regensburg Book, which formed the basis of the Regensburg Conference in place of the Augsburg Confession.

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