Evacuation
In early September, Major General George Izard's division had been ordered to march from Plattsburgh to Sackett's Harbor, where they arrived on 17 September. On 21 September, the American naval squadron on Lake Ontario under Commodore Isaac Chauncey ferried the main part of the division to the Genesee River a few miles west of the Niagara, from where they marched to reinforce Brown. Since Izard was the senior officer, he assumed command of the combined American force. The Americans now numbered 6,300 (including 800 volunteers from the militia) and had a clear advantage in numbers over Drummond, who had only 2,500 men even after further British reinforcements (the 97th Regiment) had arrived. Brown wished to make an immediate all-out attack. Izard instead waited until 13 October before he began a cautious advance, by which time the British had recovered much of their health and morale, and had strongly fortified the line of the Chippawa Creek. After some indecisive exchanges of artillery fire at the mouth of the river and a minor success against a British outpost at Cook's Mill on 19 October, Izard withdrew.
On 15 October, the British had launched the first rate ship-of-the-line HMS St. Lawrence on Lake Ontario, and Chauncey's squadron promptly withdrew into Sackett's Harbor. It was no longer possible for the Americans to move supplies to the Niagara front, except by crude roads which would be unusable during the late autumn and winter. At the same time, the British were able to reinforce and resupply their troops on the Niagara. Izard wrote to the Secretary of War (James Monroe) "At the head of the most efficient army the United States have possessed during this war, much must be expected of me; and yet I can discern no object which can be achieved at this point worthy of the risk which will attend its attempt."
At Brown's request, he and his division were transferred to Sackett's Harbor to protect the vital naval base. (The British contemplated making an attack there, but could not transport the necessary troops up the St. Lawrence before winter set in.) Izard, who was short of supplies, decided to abandon Fort Erie and go into winter quarters in New York state with the remainder of the army. On 5 November, the Americans set mines and demolished the fort before retiring across the river. This allowed the British to go into winter quarters also, which spared them losses from the winter weather. Izard himself asked for sick leave and tendered his resignation, which was refused. Many officers (including Brown) accused Izard of cowardice, and he was nearly court martialled as a result, but because of his military expertise and excellent service record, he was moved to a civil position and was eventually made Governor of Arkansas.
When the British returned to the site of Fort Erie, they chose not to rebuild the fort due to lack of funds and merely constructed makeshift quarters until completely abandoning it in 1821.
On several occasions, especially after his own failed assault on Fort Erie, General Drummond blamed his troops for lack of spirit or misbehaviour in action, but most historians consider that Drummond himself planned poorly and took insufficient care to maintain his troops' health and morale.
Read more about this topic: Siege Of Fort Erie