The Mississauga Horse was a Canadian Army militia cavalry regiment. It was originally formed as the Toronto Mounted Rifles at Toronto, Ontario on April 1, 1901, by combining J and K Squadrons of the Canadian Mounted Rifles with three newly raised companies. In 1903 the regiment was renamed to the 9th Toronto Light Horse and in 1907 it was renamed to the 9th Mississauga Horse. This was a reference to the First Nation that inhabited the area before the Europeans, the Mississaugas.