The French army, however, had been left unopposed by the Swiss (who, having arrived in Lombardy, had been bribed into leaving by Louis) and was free to march south into the heart of Italy. In early October, Charles II d'Amboise advanced on Bologna, splitting the Papal forces; by 18 October, he was only a few miles from the city. Julius now realized that the Bolognese were openly hostile to the Papacy and would not offer any resistance to the French; left with only a detachment of Venetian cavalry, he resorted to excommunicating d'Amboise, who had in the meantime been convinced by the English ambassador to avoid attacking the person of the Pope and had thus withdrawn to Ferrara.