Battle of Eccles Hill, 25 May, 1870. The Fenians were Irish Nationalists, many of them US civil war veterans, who planned to invade Canada from the US in an attempt to force Britain to restore Irish sovereignty. At Eccles Hill in Montreal, 600 Fenians clashed with Canadian Militia. A double agent betrayed the Fenians, who were repulsed. The Canadians were commanded by Lt. Col William Smith, who would later become the first commandant of the Northwest Mounted Police.