The fortress city British forces captured from France in 1759 before taking Montreal was Quebec City.
The capture followed the Battle of the Plains of Abraham on 13 September 1759, outside Quebec’s walls. British troops under James Wolfe defeated French forces commanded by Louis-Joseph de Montcalm after a lengthy siege and a daring nighttime landing above the city. Both commanders were mortally wounded, but the British victory forced the French garrison to surrender Quebec on 18 September.
Quebec’s fall was strategically crucial because it controlled the St. Lawrence River, the main route into the heart of New France. The French attempted to retake the city at the Battle of Sainte-Foy in 1760, but could not overcome the British defenses or receive adequate naval support. Later that year, British forces captured Montreal, effectively ending organized French resistance in Canada.
A common mix-up is confusing the 1759 battle with the later surrender: the battle occurred on the Plains of Abraham, while the city itself capitulated several days afterward.