World War I gave to Princess Arthur of Connaught the opportunity to embrace a vocation of nursing in which she subsequently made a highly successful career. In 1915 she joined the staff of St. Mary's Hospital, Paddington, as a full-time nurse and worked untiringly in this capacity until the armistice. After the war she continued her training at St. Mary's, becoming a state registered nurse in 1919 and being awarded a first prize for a paper on eclampsia. She also served in Queen Charlotte's Hospital where she specialized in gynaecology, receiving a certificate of merit. Throughout these years Princess Arthur increasingly impressed her superiors by her technical skill and practical efficiency.