At the outbreak of WWII, Gwynne-Vaughan became the first Director of the ATS, overseeing over 200,000 women with a rank equivalent to major-general.
At the outbreak of the Second World War in September 1939, Helen Gwynne-Vaughan was appointed the first Director of the Auxiliary Territorial Service (ATS), the women's branch of the British Army. This appointment placed her in effective command of a service that would eventually grow to encompass more than 200,000 women, holding a rank equivalent to major-general — an extraordinary level of authority for a woman at the time.
Drawing on her extensive experience leading the WAAC overseas and the WRAF during the First World War, Gwynne-Vaughan brought decades of organizational expertise to the challenge of rapidly building and structuring the ATS from the ground up as Britain mobilized for total war. The ATS women served in a vast range of roles, from anti-aircraft gun crews and dispatch riders to clerical, catering, and intelligence work, freeing men for combat duties and directly contributing to the war effort.
Her appointment as the first Director represented the culmination of her lifelong campaign to establish women's military service as a respected and integral part of Britain's defense apparatus. She fought to secure proper training standards, welfare provisions, and disciplinary structures for the servicewomen under her command, ensuring the ATS operated with the professionalism and rigor of any male military unit.
Gwynne-Vaughan's leadership of the ATS at this scale — commanding a force of hundreds of thousands of women — stands as one of the most significant achievements in the history of women's military service, and her legacy directly shaped the eventual post-war integration of women into permanent military structures.