Academic jobs in history were not easy to find in 1941, so Elliott joined the Civil Service, working in the Prices and Statistics Section of the Iron and Steel Control directorate in the Ministry of Supply. She subsequently moved to the Board of Trade, and the Directorate of Housing Fitments, where she rose to the rank of Assistant Principal, before moving to the Cabinet Office in 1945. There she became involved with the Official History of the Second World War, as assistant to Keith Hancock who was overall editor of the United Kingdom Civil Series of books within the Official History. As an official historian of the "History of the Second World War: United Kingdom Civil Series", Gowing had access to unpublished official papers and files. She came to know personally many of the politicians and senior civil servants involved.