England and France declared war on 7 May 1688 (the War of the Grand Alliance, which last from 1688 to 1697). As a result, the English greatly increased the flow of arms and ammunition to the Iroquois Confederacy. Governor Thomas Dongan of New York encouraged the Iroquois to invade Canada. In 1689, the Iroquois launched a massive offensive against the French settlements along the St. Lawrence and seized Fort Niagara and Fort Frontenac on Lake Ontario. The militia forces rushed to defend their own homes, and, as a result, Governor Denonville did not have enough regulars to garrison all the major settlements.
First, the Iroquois force besieged Lachine, where they burned 56 farms to the ground and killed over 100 inhabitants. The settlers flocked to the forts at Montreal and Trois-Rivières for protection. At night, guards on the walls could see fires raging all along the river. With the French and English now at war, the Minister of Marine recalled Governor Denonville to France and sent former governor Louis de Baude, Comte de Frontenac, back to Quebec to deal with the crisis.
