The Battle of Ridgeway was fought in the vicinity of the town of Fort Erie across the Niagara River from Buffalo, New York, near the village of Ridgeway, Canada West, currently Ontario, Canada, on June 2, 1866, between Canadian troops and an irregular army of Irish-American invaders, the Fenians. It was the largest engagement of the Fenian Raids, the first modern industrial-era battle to be fought by Canadians and the first to be fought only by Canadian troops and led exclusively by Canadian officers. The battlefield was designated a National Historic Site of Canada in 1921 and is the last battle fought within the current boundaries of Ontario against a foreign invasion.