Evan Mawdsley completed History degrees at Haverford College (Philadelphia) and the University of Chicago before returning to Britain to write a Ph.D. thesis at the University of London.
In 1970 he began work as a Lecturer at the University of Glasgow, where he eventually became Professor of International History. His initial published writing was on Russian political history from the 1917 revolution to the death of Stalin, including a general history of the Civil War of 1917–20, a short book on the Stalin era, and a study written with Stephen White on the membership of the Central Committee of the Russian Communist Party over the whole Soviet era. His interest in cultural and urban history also led to the Blue Guide to Moscow and Leningrad (co-authored with Margaret Mawdsley).
In the 2000s his work became focused on the Russian elements of the Second World War. A general history of the Soviet–German war was published in 2005 (heavily updated in the 2016 second edition). In 2011 he produced December 1941, setting in a global context a range of events including the Battle of Moscow, the Japanese attack on Malaya and Pearl Harbor, and Hitler’s declaration of war on the United States. His writing was significantly broadened out in the form of World War II: A New History, which was published in 2012 and re-published in 2020. This was supplemented by his role as general editor of the three-volume Cambridge History of the Second World War, an international project involving over seventy historians, which appeared in 2015.
His book The War for the Seas is a comprehensive history of the maritime dimension of the Second World War. This won the prestigious Anderson Medal of the Society for Nautical Research as the best maritime non-fiction book of 2019. His latest book, Supremacy at Sea: Task Force 58 and the Central Pacific Victory, was published by Yale University Press in 2024 and won the Gilder Lehrman Military History Prize.