Loius's adventure stirred up all the troubled waters of Italy, where cities were now under tyrants and where noble houses with their lands divided into petty states, acquired significance as they became more or less important pawns in dynastic diplomacy. The Guelfs were too strong to allow German rule to be consolidated, but they were not strong enough to prevent princelings and foreigners from ravaging Italy. Pope Gregory XI. ended the " captivity " by returning to Rome, but the advantages of Popes and anti-Popes and of control of a Pope in Rome, had not passed unnoticed by royal intriguers, and on Gregory's death in 1378, there began the " Great Schism," which, by weakening the Papacy and preparing the ground for the Reformation, was to provoke a greater rent in Christendom than any of the schismatics had anticipated. 'Two Popes ruled, each mutually declaring the other anti-pope, Urban VI. in Rome and Clement VII. in Avignon. Each received strong support, but the support was given purely on political lines. Austria, Bohemia, Hungary, and England supported Urban; France and Scotland, Clement.

In 1347 Charles IV., the son of John of Luxemburg, added to the throne of Bohemia the dignity of the Empire. The title was a meaningless one, for his rule was hardly recognised, and the parts of the Empire were pursuing their own national policies. On the other hand, he did much for Bohemia, founding the University of Prague, reforming the finances, encouraging industry, and attempting to codify the laws. The result of the weak rule of his son and successor, Wenceslas, was a formidable explosion of Bohemian nationalism on the part of a nation which had to watch Louis of Hungary take Dalmatia from Venice and become the greatest monarch in Central Europe, and Poland set her feet on the road on which she was to become a great power. Wenceslas was deposed from the Empire, which had gone to a Bavarian, Rupert of the Palatinate, but on his death Charles's second son, Sigismund, became emperor, and it was he who in the presence of nationalism and heresy sought at the dawn of the new era to deal firmly with schism.

The house of Luxemburg could produce obstinate men, and Sigismund hammered away at the problem till he got a solution. That it came hopelessly late was not his fault. His father, the Emperor Charles IV., had defined the duties of the electors,1 and given the electoral college definite status. Individually, the electors might be very minor potentates and venal at that, but collectively they elected, and so in a sense stood above the Emperor. By analogy it was suggested that a General Council of the Church might override the Pope. There were plenty of precedents and, if there might have been hesitation to place an Innocent III. at the mercy of a council, there could be no objection to placing the decision as to the claims of three men to be Pope, each engaged in anathematising the rest, in the hands of a council which would represent the sanctity and the intelligence of the Catholic Church. Sigismund held to the plan with praiseworthy resolution. A council at Pisa deposed both the Avignon and the Roman Popes, and elected Alexander V. to the chair of St. Peter.

But this was only a beginning. Mere arithmetical reduction of Popes reigning simultaneously was not of itself enough to reform a Church that was now being seriously threatened by heresy, and to save a Christendom that was being menaced by the infidel. Sigismund. succeeded in having the great Council of Constance summoned. The council deposed Popes, sat off and on for four years (1414-18), passed all sorts of reform schemes, was the scene of a bitter diplomatic conflict between national states, and healed the schism by electing Martin V. But it did something far more epoch-making than end the

1 Electors: the four princes and three Church dignitaries in whom was invested the right to elect the Emperor. schism; in 1415 it burned at the stake John Huss, the Bohemian anti-Papal religious reformer.