The difficulties of the youthful commander were increased by the inopportune arrival of four thousand Swiss mercenaries, who, finding matters in train for a pacification which would dash their hopes of booty, could scarcely be restrained from an immediate assault upon Ravenna. Their ruffianly intentions being insidiously encouraged by the Legate, it was only by great prudence and decision that the Duke prevented them from sacking that city, when evacuated on honourable terms by the Venetian authorities. This conciliatory policy was rewarded by a speedy surrender of Cervia, followed on the 11th of June by that of Rimini, the last of the towns claimed by Julius, upon which Francesco Maria lost no time in disbanding his army and returning home. As soon as he was gone, the Cardinal, steady only to his duplicity, imprisoned the Venetian officers who had imprudently lingered within his reach. Although this campaign lasted but six weeks, and produced no considerable engagement, it afforded to the young Duke an insight into mankind, as well as a lesson in military affairs, which enabled him to pass at once from boyhood to the experience, as well as the reputation, of an able commander. As soon as Francesco Maria was liberated from camp duties, he sent to Mantua for his bride, and at his uncle's desire carried her to visit Rome. The Roman citizens, ever devoted to festivity, received him with distinction, due not less to his personal merit than to his high rank and near relationship to the Pope. Among the pageants exhibited in honour of his marriage were tilting in the Piazza Navona, and a masque celebrating his successes in Romagna, after the manner of those triumphs which that capital used to witness some fifteen centuries before. He carried Giuliano de' Medici with him to the papal court, and effected his reconciliation with Julius, who, suspecting him of some intrigues at Bologna, had given orders for his imprisonment; thus swelling that debt of the Medici to his family, which Leo X. subsequently and most ungratefully expunged.