During the negotiations of Rudolph with Gregory X, Ottocar had exerted himself to shake the authority of the new chief of the empire, and to consolidate a confederacy with the German princes.  He not only rejected with disdain all the proposals of accommodation made at the instances of Rudolph by the judicious and conciliating Pontiff, but prevented the clergy of Bohemia from contributing the tenths of their revenue or preaching the crusade.  He endeavored to alarm the princes of the empire by displaying the views of the new sovereign, to recover the imperial fiefs which they had appropriated during the interregnum, and by his promises and intrigues succeeded in attaching to his cause the Margrave of Baden and the counts of Freiburg, Neuburg, and Montfort.  But he secured a still more powerful partisan in Henry, Duke of Lower Bavaria, by fomenting the disputes between him and his brother the Count Palatine, and by ceding to him Scharding and other places wrested from Bavaria by the Duke of Austria.

When summoned by Rudolph to do homage for his fiefs, according to the custom of the empire, he returned a haughty answer, treating him as Count of Hapsburg; a second summons was received with silent contempt; on a third he sent his ambassador, the Bishop of Seccan, to the Diet of Augsburg; and his example was followed by Henry of Bavaria.  These ministers were, however, only deputed to raise a feigned contest relative to the vote of Henry and to protest against the election of Rudolph.  The ambassador of Henry urged the protest with moderation and respect; but the Bishop of Seccan delivered a virulent invective against the chief of the empire, in a style conformable to the spirit and character of his powerful and haughty master.  He declared that the assembly in which Rudolph had been chosen was illegal; that the arbitration of Louis of Bavaria was unprecedented; that a man excommunicated by the Pope for plundering churches and convents was ineligible to the imperial throne, and that his sovereign, who held his dominions by an indisputable title, owed no homage to the Count of Hapsburg.

As he spoke in the Latin tongue, the Emperor interrupted him with a dignified rebuke.  “Bishop,” he said, “if you were to harangue in an ecclesiastical consistory, you might use the Latin tongue; but when discoursing upon your rights and the rights of the princes of the empire, why do you employ a language which the greater part of those who are present do not comprehend?” The rebuke of the sovereign justly roused the indignation of the assembly; the princes, and particularly the Elector Palatine, started from their seats, and were scarcely prevented from employing violence, even by the interposition of Rudolph; and the ambassadors, quitting the assembly, retired from Augsburg.