Battle of Fort Niagara The Battle of Fort Niagara was a siege late in the French and Indian War , the North American theatre of the Seven Years ' War . The British siege of Fort Niagara in July 1759 was part of a campaign to remove French control of the Great Lakes and Ohio Valley regions , making possible a western invasion of the French province of Canada in conjunction with General James Wolfe ' s invasion to the east . Background . British General Jeffrey Amherst made plans for the 1759 military campaigns of the French and Indian War that included an expedition to capture Fort Niagara , a major French military and supply point between the French province of Canada and their forts in the Ohio Valley . Amherst chose Brigadier General John Prideaux to lead the expedition , which also included Sir William Johnson , the British Indian agent who led the expedition ' s Iroquois forces . Fort Niagara had been largely constructed under the direction of Captain Pierre Pouchot of the French Army . In early 1759 , General Louis - Joseph de Montcalm and New France ' s Governor , the Marquis de Vaudreuil , sent him with about 2 , 500 men to fortify Niagara beyond the 500 men that had wintered there . Pouchot , under orders from Vaudreuil , sent many of those men south to Fort Machault in mid - June as part of a plan to reinforce the French forts of the Ohio Country and attack the British at Fort Pitt . The forces left to defend Niagara consisted of about 200 men from the regiments of Royal Roussillon , Languedoc , La Sarre , and Béarn , 20 artillerymen , and about 300 provincial troops and militia . Prideaux ' s British Army troops consisted of the 44th and 46th Regiments , and two companies from the 60th , numbering about 2 , 200 men . He also commanded 2500 provincial militia from New York and 700 from Rhode Island . Delayed by high water on the Mohawk River and the late arrival of some of the provincial companies , the expedition did not begin leaving Schenectady until mid - May . On 27 June the army arrived at Fort Oswego , where they were joined by Johnson and about 600 Iroquois . Leaving men behind to garrison Oswego , Prideaux departed on 1 July for Niagara with about 3 , 500 men . While the French had ships patrolling Lake Ontario for British movements , inattention on the part of one the crews allowed the British flotilla to avoid discovery . They arrived at Fort Niagara on 6 July , landed near a marsh out of sight of the fort , and immediately began siege operations . Siege . The French had about one hundred Iroquois allies at the Fort who deserted when the British arrived . Captain Pouchot directed a vigorous defense . Prideaux was killed when a shell fragment from one of his own guns hit him , and command of the British forces fell to Sir William Johnson . Johnson was a provincial officer and not in the regular army , and thus there was some question of his right to take command . But Sir William held a royal colonel ' s commission in his role as commander of the Iroquois auxiliaries , and so he insisted on remaining in command after a lower - ranking regular army officer , Lieutenant Colonel Frederick Haldimand , arrived on the scene . The French capitulated on 26 July after a French relief force was defeated at the Battle of La Belle - Famille two miles south of the fort . Aftermath . The capitulation of Fort Niagara occurred on the same day that French troops abandoned Fort Carillon to an overwhelming British army under General Amherst . Fort St . Frédéric was also destroyed as French troops abandoned Lake Champlain to protect the Canadian heartland . Most French forces were at Quebec , where Montcalm was leading the defences against Wolfe ' s siege . Quebec fell in September 1759 , and all of New France was surrendered in September 1760 . The remaining French forts in the Ohio and Illinois Country were eventually turned over to British forces .