As part of a British plan to remove French forts from the Great Lakes and Ohio River Valley, for the purposes of invading New France from three different directions, British forces under the command of General John Prideaux and William Johnson defeated the French resistance in a 20-day long siege on July 26, 1759.

As a result of the defeat, the French were forced to abandon several other forts and consolidate their forces for the defense of Quebec City. They also gave up a crucial supply center for their western forts. For the British, the victory at Fort Niagara meant control of the eastern Great Lakes.