But the great victory of the year was the capture of Quebec. To secure Canada was one of Pitt's chief objects. Louisburg and Duquesne had already fallen, and the country itself was thus open to his attack. The French army was under the command of an excellent general, the Marquis de Montcalm, who had his headquarters at Quebec. General Amherst was the English commander-in-chief, but subordinates of more than usual vigour were necessary for him, and Pitt, who had kept his eye on Wolfe since the attack on Rochefort, and had seen his energy at the siege of Louisburg, disregarding all claims of seniority, intrusted to him the attack on Quebec. This was originally to be a combined movement. Amherst was to march up by Lakes Champlain and George, take Ticonderoga and Crown Point, where Abercrombie had failed last year, and thus reach the St. Lawrence. Generals Prideaux and Johnson were to take Fort Niagara, and then, passing down Lake Ontario into the St. Lawrence, to join in the attack on Quebec, securing Montreal on the way. Though both these latter expeditions were successful, the difficulties met with rendered them so slow that the combination failed. The plan was Pitt's own, and was probably too extensive; it may be doubted whether he had sufficient knowledge of what it is possible for an army to do. Wolfe, with 8000 men, embarked in the squadron of Admiral Saunders, and reached the Isle of Orleans in the St. Lawrence river on the 13th of June. The expedition experienced no disasters in the way, having fortunately captured a vessel with some excellent charts of the river.