During the fall and winter of 1758-1759, the Governor of New France, Pierre de Rigaud, marquis de Vaudreuil, and the Commander of the metropolitan land forces, Louis-Joseph, marquis de Montcalm, developed a strategy to defend the colony. The two men, who had a stormy relationship, had diametrically opposite views on the procedure to follow. On the one hand, Montcalm thought that the British army was too large, and this would not allow them to defend all of New France's borders. Considering the men, food and ammunition he had available, it was the General's opinion that the colony's defensive area must be reduced and all the forces assigned to this single area. On the contrary, Vaudreuil thought that it was necessary to carry the war to the limits of the colony. According to him, a small number of men were needed to keep most of the enemy busy.
At the dawn of 1759, the situation in New France was precarious. Although Montcalm had won a victory at Fort Carillon the previous year, it seemed obvious to the French court that the British would try another show of strength. In Versailles, it was also known that Montcalm and Vaudreuil were not in good terms, and that there was corruption in the colony. So what could be done?
At the end of 1758, the colonial authorities sent an emissary to meet with the King and his ministers and request the support of the capital. This emissary was Louis-Antoine de Bougainville, Montcalm's aide-de-camp. The General's demands were in fact moderate. He was aware that it would be very difficult to send large-scale reinforcements in view of the British naval superiority. He therefore suggested that the French strategy rely on the diversion principle. If France was to attack the American colonies of Virginia and the Carolinas, which were poorly defended, the British would be forced to divide up their troops. It was also possible to instigate a slave uprising. Concerning direct assistance, Montcalm pleaded for the dispatching of artillerymen and engineers, as well as large quantities of ammunitions, artillery, weapons, and various supplies to be later exchanged with the Amerindians.
When, on May 10, 1759, Bougainville returned to Québec City from his French mission, he found out that Vaudreuil and Montcalm were in Montreal. So, he sent letters to them which he had brought back from Versailles. Some of them warned that the British were getting ready to go upriver and attack the heart of the colony. Montcalm therefore left Montreal for Québec, where he arrived on the evening of May 22. The next day, he was informed that British ships were at Saint-Barnabé, near Rimouski. The General therefore organized the city's defence: a trench was dug in Beauport; the regiments that had spent the winter in Trois-Rivières and Montreal were recalled; two ships were sunk at the mouth of the St. Charles River to block this access route and to put up batteries; and the population was ordered to hide the women, children and animals deep in the woods, etc. Fire ships were readied: these were small crafts filled with flammable debris to be sent out against the British fleet to set it on fire.
The General also made another decision that would deeply impact the rest of the campaign. On June 1st, he ordered that stocks and ammunitions be stored in a safe place upstream from Québec, namely at Batiscan and as far as Trois-Rivières, to prevent their falling into British hands if the city was captured. However, this strategy was based on the false assumption that the British could not gain control of the river upstream.
Be that as it may, when Wolfe's army arrived on June 27, 1759, the most vulnerable spot for a landing, the Beauport Flats, were protected by defence works and by a majority of the valid men, thanks to the measures implemented by Montcalm the previous May.
From a more theoretical perspective, in the face of the British invasion, Montcalm's strategy was mostly defensive and focused on the eastern part of the city. Thus, the Beauport Flats and the Montmorency River especially drew Montcalm's attention. Several defence works were brought into play to secure the city: landing stage, wall, trench, stockade, redoubt, fire ship, bastion81.
Montcalm's defensive efforts were almost exclusively centered on the north shore, resulting in the relinquishment of major south shore positions into enemy hands, as at the Île d'Orléans and in Levis. From a naval perspective, here again, few actions were taken to ensure the dominion over the river – Montcalm thought that no ship of importance could sail past Québec because of the navigation problems on the river. We should however mention another strategy put to use when the British fleet was approaching in June: navigation aids were removed off the Île d'Orléans (the "Traverse"), and they were replaced by false ones. On the French side, high hopes were placed on this natural obstacle. However, it took the British Navy only a few days to recognize the "Traverse", that is, the navigation route leading from Cap Tourmente to the southern part of the Île d'Orléans, and so open the way to Québec.
The offensive efforts of the French Army to defend the city were few. In July, Montcalm hoped to launch an expedition to dislodge the British from the other side of the Montmorency River, but the officers opted instead for a cautious defence strategy. Moreover, the few attacks led by the French proved to be catastrophic for them, such as the fire ships, or the expedition launched to dislodge the British from Pointe-Lévy. This expedition failed even before the detachment had a chance to approach the enemy.
In short, the strategy developed by Montcalm and Vaudreuil at the siege of 1759 was almost exclusively defensive, and they largely relied on reinforcements from the capital – which never came – and on the natural defences of the city to guarantee their supremacy during the confrontations. Well, as infallible as these natural boundaries may have seemed, they turned out to be insufficient to stop the British.