The Battle of Fort Oswego was one in a series of early French victories in the North American theatre of the Seven Years' War won in spite of New France's military vulnerability. During the week of August 10, 1756, a force of regulars and Canadian militia under General Montcalm captured and occupied the British fortifications at Fort Oswego, located at the site of present-day Oswego, New York. In addition to 1,700 prisoners, Montcalm's force seized the fort's 121 cannons. The fall of Fort Oswego effectively interrupted the British presence on Lake Ontario and removed it as a threat to the nearby French-controlled Fort Frontenac. The battle was notable for demonstrating that traditional European siege tactics were viable in North America when applied properly in the right circumstances and terrain. Background Following the beginning of open conflict between French and British colonists in 1754 with the Battle of Jumonville Glen, the governments of Britain and France both sent regular army troops to North America to further contest the disputed territories of the Ohio Country and other border areas, including the frontier between the French province of Canada and the British province of New York, an area in present-day Upstate New York that was then largely controlled by the Iroquois nations. Part of the British plans for 1755 included an expedition to take Fort Niagara at the western end of Lake Ontario. Under the direction of William Shirley, the governor of the Province of Massachusetts Bay, the original Fort Oswego was reinforced, and two additional forts, Fort George and Fort Ontario, were built in 1755. The planned expedition to Fort Niagara never took place due to logistical difficulties, and the fortifications around Oswego were manned during the winter of 1755–56. The French in 1755 had the only large naval vessels on Lake Ontario, and moved freely about the lake, between Fort Niagara in the west and Fort Frontenac at the head of the Saint Lawrence River. In March 1756 they launched a winter attack on Fort Bull on Wood Creek. Fort Bull was a key depot on the supply line for the Oswego forts, which was the waterway leading up the Mohawk River and crossing over to the Oswego River watershed. In the successful attack, they destroyed many provisions intended for the Oswego garrison, and effectively ruined Shirley's plan to attempt the expedition against Fort Niagara in 1756. Following orders of the