During the French and Indian War, the Oswego River was the only British-controlled waterway into the Great Lakes, making Oswego a strategic link to the Five Nations, Albany, and the Hudson River and a position defended by Fort Ontario on the right bank and Forts George and Chouaguen, or Oswego, on the left. England’s first presence on the Great Lakes began in 1727 when a stone blockhouse called Fort Oswego was built beside a growing trader’s settlement. In the 1740s, a seasonal village flourished as hundreds of Dutch and English fur traders lived in more than seventy log huts and traded with American Indians, and from 1741 to 1743 Fort Oswego was strengthened with an outer U-shaped stone wall. In 1752, the fort’s garrison of eight men mutinied and placed their lone officer in irons. In 1755, Major General William Shirley strengthened Fort Oswego, built Forts George and Ontario, and established the Royal Navy’s first Great Lakes squadron in the harbor. Fort George, known as Fort Beef or Fort Rascal, was an unfinished log-and-earth work little better than a cattle pen and was garrisoned by the provincial force called the Jersey Blues, while Fort Oswego was a castle-like stone fort whose low ground and mud-mortared masonry left it vulnerable to artillery despite its strong appearance. During the winter of 1755 to 1756, the seven hundred troops left at the forts were decimated by disease and starvation, with more than half dead by spring, and in spring 1756 the troops were harassed by American Indian and Canadian raiders. In August 1756, with more than three thousand French, Indians, and Canadians, the Marquis de Montcalm drove the British from Fort Ontario, forced them back across the river to Fort Oswego, sent fifteen hundred Indians and Canadians across the river to surround the west-side forts, and moved artillery to high ground on the east side of the harbor to bombard Fort Oswego. As British commander Colonel James Mercer prepared a breakout attempt with five hundred men, a cannonball killed him; Lieutenant Colonel John Littlehales then quickly sought a parley and surrendered. The British loss was catastrophic: three forts, eleven hundred soldiers and sailors, six hundred civilians including skilled craftsmen, the trader’s village, a new fleet of seven ships, and more than one hundred pieces of ordnance. Oswego was wiped from the map, Lake Ontario became French again, and because Montcalm failed to hold the ground, the British returned and reoccupied Oswego in 1759.