As honoured guests were to be found attending on him humanists, poets, minstrels, partisans of the new theology, astrologers, alchemists, and men of letters generally--in short, the whole intelligence and culture of the period.

Foremost amongst these, and chief confidant of Sickingen, was the knight, courtier, poet, essayist, and pamphleteer, Ulrich von Hutten, whose pen was ever ready to champion with unstinted enthusiasm the cause of the progressive ideas of his age.

He first took up the cudgels against the obscurantists on behalf of Humanism as represented by Erasmus and Reuchlin, the latter of whom he bravely defended in his dispute with the Inquisition and the monks of Cologne, and in his contributions to the _Epistolae Obscurorum Virorum_ we see the youthful ardour of the Renaissance in full blast in its onslaught on the forces of mediaeval obstruction.

Unlike most of those with whom he was first associated, Hutten passed from being the upholder of the New Learning to the role of champion of the Reformation; and it was largely through his influence that Sickingen took up the cause of Luther and his movement.
Sickingen had been induced by Charles V to assist him in an abortive attempt to invade France in 1521, from which campaign he had returned without much benefit either material or moral, save that Charles was left heavily in his debt.

The accumulated hatred of generations for the priesthood had made Sickingen a willing instrument in the hands of the reforming party, and believing that Charles now lay to some extent in his power, he considered the moment opportune for putting his long-cherished scheme into operation for reforming the Constitution of the empire.