Hubert was born in Sandhurst, Bendigo on 6 July 1876 to Albert Bush and Jane Dalton. He was the second youngest of 11 children. His early life was spent in Sandhurst where he attended St. Andrew's College, Bendigo before entering Trinity College, University of Melbourne in 1898 to study Medicine. At Trinity College he was a member of  both the boat and football teams. In 1904 he was a Medical Tutor at Trinity, graduating with his MBBS in 1906. From here he became a Surgeon to outpatients and a Surgical Tutor at St Vincent's Hospital, Melbourne. In 1906 he married Louisa Ann Reynolds in Bendigo.

In 1909 Hubert and Louisa were living in Rutherglen, Victoria where he had a medical practice. They remained in Rutherglen until around the time of enlistment on 21 August 1916, when he and Louisa were living at 52 Powlett Street, East Melbourne. Hubert had moved his practice to 110 Collins Street, Melbourne.

Appointed Captain upon enlistment, he joined the AMC General Reinforcements, and embarked ex Sydney on the Euripides on 9 September 1916, disembarking at Plymouth on 26 October 1916. Based at the AIF headquarters London, he was taken on strength by the 2nd Australian General Hospital at Wimereaux, near Calais, France on  3 December 1916. He remained in Wimereux till March 1918, with the 2nd AGH until January 1918, when he proceeded to temporary duty with the DMS 1st Army. Early March 1918 he transferrred to the 1st AGH as surgeon with the surgical team based in Rouen. In July 1918 he joined the Surgical team with te 2nd Army before transferring t the 55th CCS in the Field in August. Soon was hospitalised with dysentery, then evacuated to the London General Hospital, Wandsworth with Influenza which left Hubert very debilitated and unable to continue his medical service. He returned to Australia 31 March 1919 on the Wandilla, appointed  ships adjutant. His appointment was terminated 14 August 1919.

In 1919, Hubert and Louisa moved to 314 Orrong Road, Toorak where Hubert remained until his death in 1964. He resumed his medical practice in Collins Street after returning form the War. His service records show that he applied for Repatriation Benefits on 20 April 1964, however there is no evidence of approval.