Born in Bertie Township, Cruikshank worked as a journalist and translator before being commissioned in the 44th Welland Battalion in 1877. Rising to the rank of Brigadier-General in 1915, he commanded Military District 13 before becoming Director of the historical section of the general staff (1917-20). Chairman of the Historic Sites and Monuments Board of Canada from its creation in 1919 until his death, he was the author of many papers and several books on Ontario and Canadian history. He was elected F.R.S.C. in 1905 and awarded the Tyrrell Gold Medal for historical research in 1935. He died at Ottawa.