The newly arrived Imperial governors, however, quickly proved to be unpopular. In mid-July, the citizens of Padua, aided by detachments of Venetian cavalry under the command of the proveditor Andrea Gritti, revolted. The landsknechts garrisoning the city were too few in number to mount effective resistance, and Padua was restored to Venetian control on 17 July. The success of the revolt finally pushed Maximilian into action. In early August, a massive Imperial army, accompanied by bodies of French and Spanish troops, set out from Trento into the Veneto. Because of a lack of horses, as well as general disorganization, Maximilian's forces were slow to begin the Siege of Padua, giving Pitigliano the time to concentrate such troops as were still available to him in the city. Although French and Imperial artillery successfully breached Padua's walls, the defenders managed to hold the city until Maximilian, growing impatient, lifted the siege on 1 October and withdrew to Tyrol with the main part of his army.