Gavin Merrick Long OBE (31 May 1901 – 10 October 1968) was an Australian journalist and military historian. He was the general editor of the official history series Australia in the War of 1939–1945 and the author of three of its 22 volumes. Gavin Long was born in Foster, Victoria, the eldest of six children of George Merrick Long, a clergyman. He was educated at Trinity Grammar School where his father was headmaster, and All Saints College, Bathurst.