A turning point came in 1777 when British forces invaded New York from Canada and laid siege to Patriots in Fort Stanwix. In August, when Brant learned that a large body of Patriot militia was on its way to relieve the fort, she sent Mohawk runners to alert the British commander of the danger. This information enabled a British, Mohawk, and Seneca force to ambush the Patriots and their Oneida allies in the Battle of Oriskany. The Iroquois were divided in their loyalties. The Oneida allied with the Patriots, while most bands of the other four nations allied with the British. After this battle, in which Iroquois warriors of these nations fought on both sides, the war in the Mohawk Valley became particularly brutal. The Oneida and rebel Americans retaliated against Brant by pillaging Canajoharie. Brant fled with her children to Onondaga, the central city of the Iroquois Confederacy. Her departure was so precipitate that she had to leave most of her belongings behind.