Met in 1431, and labored for 12 years to effect the reformation of the Church from within. It effected some compromise with the Hussites, but was hampered at every step by the opposition of Pope Eugenius IV. Asserting the authority of a general council over the Pope himself, it cited him on two occasions to appear at its bar, on his refusal declared him contumacious, and ultimately endeavoured to suspend him. Failing to effect its purpose, owing to the secession of his supporters, it elected a rival pope, Felix V., who was, however, but scantily recognised. The Emperor Frederick III. supported Eugenius, and the council gradually melted away. At length, in 1449, the pope died, Felix resigned, and Nicholas V. was recognised by the whole Church. The decrees of the council were directed against the immorality of the clergy, the indecorousness of certain festivals, the papal prerogatives and exactions, and dealt with the election of popes and the procedure of the College of Cardinals. They were all confirmed by Nicholas V., but are not recognised by modern Roman canonists.