The name of this lake was assigned in 1931 as part of a systematic designation of bodies of water in Laurentides Park. The designations were intended to honour soldiers of the Royal 22nd Regiment who fought in the First World War. Lieutenant August-Isaïe Morency was born in 1889 in Saint-Romuald, Levis, Quebec. He enlisted in Valcartier, in June 1915, in the 57th Battalion. He was transferred to the 22nd Battalion, Canadian Infantry (Quebec Regiment), later designated as the Royal 22nd Regiment. He died in September 1916, during the Battle of Courcelette, France.