During the early months of 1814, while
Lake Ontario was frozen, the British and American naval squadrons had been building two
frigates each, with which to contest command of the lake during the coming campaigning season. The British under Commodore Sir
James Lucas Yeo were first to complete their frigates on 14 April, but when the Americans under Commodore
Isaac Chauncey had completed their own, more powerful, frigates, Yeo's squadron would be outclassed. Lieutenant General Sir
Gordon Drummond, the Lieutenant Governor of
Upper Canada, suggested using the interval during which Yeo's squadron was stronger than Chauncey's to attack the main American harbour and base at
Sackett's Harbor, New York. Most of its garrison had marched off to the
Niagara River, leaving only 1,000 regular troops as its garrison. Nevertheless, Drummond would require reinforcements to mount a successful attack on the strongly fortified town, and the Governor General of Canada, Lieutenant General Sir
George Prevost, refused to provide these. Instead, Drummond and Yeo decided to attack the smaller post at
Fort Ontario. This fort, with the nearby village of
Oswego, New York, was a vital staging point on the American supply route from
New York. Ordnance, food and other supplies were carried up the
Mohawk River and across
Lake Oneida, to Oswego, before making the final leg of the journey across the southeast corner of Lake Ontario to
Sackett's Harbor. Drummond and Yeo had reliable information that the garrison of the fort numbered only 290 regulars, and believed that thirty or more heavy guns intended for Chauncey's ships under construction at Sackett's Harbor were waiting there. They planned, by capturing Oswego, to capture these guns and thereby retain Yeo's advantage over Chauncey. ==Attack==