In some ways Urban was more uncompromising than his master Gregory. He upheld the papal legates in their strict treatment of the French bishops; he actually launched against Philip I of France the excommunication which Gregory had only threatened; to the prohibition of lay investiture he added an explicit command that bishops and clergy should not do homage to any layman. But while he showed himself thus in thorough sympathy with his predecessor, in his power of dealing with circumstances he proved himself by far the superior. A succession of clever if thoroughly unscrupulous measures restored the fortunes of the papal party. Henry had succeeded for the moment in dividing and isolating his enemies. Urban set himself to unite the chief opponents of Henry on both sides of the Alps. He planned a marriage between the middle-aged widow, the Countess Matilda of Tuscany, and the eighteen-year-old son of Welf, Duke of Bavaria (1089). Matilda was ready to sacrifice herself for the good of the cause. The Welfs, ignorant of Matilda's gift of her lands to the Papacy, eagerly accepted the bait; but soon discovering that they were being used as tools, they ceased to give any help, and in fact became reconciled to the Emperor. But meanwhile the Pope had discovered other more deadly weapons with which to wound the Emperor. The deaths of the anti-Kings had left the papal party without a leader in Germany. Events had shown the firm hold of the hereditary claim and the Salian House upon a large portion of the Empire. The only acceptable leader would be a member of Henry's own house. Henry's actions played into their hands. His eldest son, Conrad, had been crowned at Aachen in 1087 and sent into Italy to act as his father's representative. He is described as a young man of studious and dreamy character, unpractical and easily influenced. In 1087 Henry lost his faithful wife Bertha, and a year later he married a Russian Princess, Praxedis, who was the widow of the Count of the Northern March. The marriage was unhappy; each accused the other of misconduct; and Henry, suspecting the relations of Conrad with his stepmother, put them both in prison. Perhaps Conrad had already been worked upon by the papal party. He escaped, took refuge with the Countess Matilda, and was crowned King of Italy (1093). But he was only the tool of others. Far more immediately dangerous was the escape of Praxedis (1094), who laid before the Pope the foulest charges against Henry. To her lasting shame the Countess Matilda was the chief agent in these family revolts. The effect on Henry's position in Italy was disastrous. Pope Urban finally recovered Rome, and Conrad, having won the cities of Lombardy, took an oath of fealty to the Papacy in return for a promise of the Empire. [Sidenote: Beginning of the Crusades.]