This opportunity was eagerly seized by Sigismund. He had never formally resigned that administrative power which Wenceslaus had granted to him in his time of emergency; and, though he had nominally supported Wenceslaus against Rupert in his claim to the Imperial crown, he was now intriguing to succeed the latter and to set aside his brother. Wenceslaus, on his part, was willing enough to listen to proposals for peace when they did not come from a clerical source; and Zbynĕk consented to accept the arbitration proposed. But, when the arbitrators demanded that the archbishop should write to the Pope to ask him to repeal the excommunication of Hus, Zbynĕk refused to submit to this decision; and he went to Presburg to appeal personally to Sigismund. There, however, he fell ill and died; and, in a few months, the controversy had assumed quite another form.
It will be remembered that the Council of Pisa had professed to put an end to the disunion in the Church by deposing the two claimants of the Papacy, and electing Alexander V. in their place. But, though Alexander V., and his successor, John XXIII., had probably been accepted by a majority of the authorities of the Church, the deposed Popes still, at times, put forward claims which could easily be taken advantage of by those who wished to stir up division in the Church. Ladislaus, the king of Naples, who had a grudge against John, took up the cause of Gregory XII. Therefore, in December, 1411, John proclaimed a crusade against the King of Naples, and promised plenary indulgence to all who would support this expedition, either in purse or person.
The commissioners for promoting this war arrived in Prague in 1412; and they soon set to work, not merely to preach the crusade, but to organise a regular system for the sale of the indulgences. Some attempt to start this trade had been begun in 1393, but it does not seem to have been then carried on on so extensive a scale. _Now_ the Legate farmed out the right of selling these indulgences to other priests, granting them preferment in the Church, and receiving from them a commission on what they raised. As respectable clergymen would not often undertake such an office, the trade fell into the hands of men of disreputable lives, who were thus brought prominently to the front. Hus had objected, from the first, to the attempt to involve the Bohemians in a war which he considered unchristian; and, when to the proposal for the crusade was added the organisation of the sale of indulgences, he determined to raise the question in an assembly of the University.