Margaret Walker Bevan was born in Swansea on 22 October 1883, the elder of two daughters to John and Harriet Bevan. In May 1902 she became a trainee nurse in Coventry City Hospital. On completion of her basic training, she joined the Becket Hospital in Barnsley, rising to the position of Matron by the time she resigned in 1915. She joined the Welsh Military Hospital, Netley (near Southampton) in July 1915, volunteering for overseas service. The hospital, maintained by voluntary contributions from Wales, had 399 beds and was treating casualties of the Great War within weeks of the British Expeditionary Force crossing the channel in 1914. In May 1915 the Commanding Officer received orders to take the Welch (sic) Hospital overseas to India as a complete unit with staff and equipment for 3000 beds. It was known as the 34th Welch General Hospital, Deolali, India, and the nursing staff had to join The Queen Alexandra's Imperial Military Nursing Service (QAIMNS). The staff sailed to Bombay (via Alexandria) on H M Hospital Ship Valdivia.