Gwynne Dyer was born in St. John's Newfoundland and educated at Memorial University (BA 1963), Rice University, Texas (MA, Military history, 1966) and the University of London (PhD, Military and Middle Eastern History, 1973). Dyer served in the Canadian, American and British navies. He was a lecturer in Military History at Canadian Forces College, Toronto (1964-1966); a senior lecturer in War Studies at the Royal Military Academy, Sandhurst (1973-1977) and an Associate Fellow in Middle Eastern Studies at the University of Oxford (1973-1975).

Dyer has worked as a freelance journalist, broadcaster and lecturer since leaving teaching in the 1970s. His syndicated columns on international affairs appear in a dozen languages in nearly 200 newspapers published in 40 countries around the world. Dyer, in collaboration with Tina Viljoen, has created a number of television series and radio documentaries on topics related to war, human politics and peacekeeping.