By 1814, the Americans controlled all of Ohio,[14] all of Indiana,[15] Illinois south of Peoria,[16] and the Detroit region of Michigan.[17] The British and their Indian allies controlled the rest of Michigan and all of Wisconsin.[18] With the Americans in control of Lake Erie and Southwestern Upper Canada, the British were largely cut off from their units in Michigan and Wisconsin. Reinforcing them, and even bringing in supplies of guns and gunpowder, was quite difficult. At all times the American negotiators at Ghent in 1814 refused to negotiate any buffer state whatsoever.