Mary Ann 'Bessie' Pocock was born to George and Mary Pocock on 20 July 1863 at Dalby, Queensland. Bessie joined the New South Wales Army Nursing Service Reserve (NSWANSR) and was one of fourteen selected from the NSWANSR to accompany the New South Wales second contingent to the Boer War. Bessie departed on SS Moravian on 17 January 1900 and after disembarking at Cape Town was posted to the 2nd Stationary Hospital, East London. In July-August she moved to the 17th Stationary Hospital, Middleburg, Transvaal, where she served as the sister-in-charge. After contracting enteric fever she was invalided to England in May 1902, returning to Sydney in April the following year. For her service, Bessie was awarded the King's and Queen's South Africa medals.

After the outbreak of the First World War, Bessie enlisted with the Australian Imperial Force (AIF) on 15 October 1914. She departed Australia on the SS Argylshire on 18 October 1914 and, after arriving in Egypt, took up her duties with the 2nd Australian General Hospital (2AGH) in Cairo. For the first part of 1915, Bessie was in charge of a temporary hospital for wounded situated in Ismailia. From July 1915 to January 1916 she served as matron on the hospital ship Assaye, which evacuated and treated wounded on a round trip from Alexandria to Gallipoli to Malta to England and then back to Alexandria.

On 30 January 1916, Bessie was appointed the temporary matron-in-charge of the Australian convalescent depot at Mena, Egypt. She was also mentioned in despatches for her work. From April to July, Bessie served with the 2nd Australian General Hospital at Marseilles and Wimereux as a senior sister. She was then dispatched to act as matron at the 2nd Australian Casualty Clearing Station at Trois Arbes in Belgium until April 1917. Bessie later re-joined the 2AGH at Boulogne before taking charge of the Australian convalescent hospital at Cobham Hall in Kent in October. Bessie's final appointment was at the 3rd Australian Auxiliary Hospital at Dartford, England, from January 1918 to January 1919. She was awarded the Royal Red Cross, 2nd Class (ARRC) in May 1916 and was twice mentioned in despatches. Bessie returned to Australia on SS Zealandia in May 1919 and was discharged from the AIF on 30 October 1919.

In 1924 she established and ran a convalescent hospital at Chatswood, which she named 'Ismailia' after her time in Egypt. Mary Anne 'Bessie' Pocock returned to Grafton in the late 1930s, where she passed away on 16 July 1946.