Hall also won an Inglis Studentship that allowed him to gain a Master's degree from the University of London with a thesis on mercantile aspects of English foreign policy during the reign of Charles II.
During the First World War Hall served in the army with Inns of Court Regiment, and also toured the Western Front with the Lena Ashworth concert party.
The completion of further research, including The Dalhousie-Phayre Correspondence, led to Hall being awarded a degree of Doctor of Literature by the University of London.
In 1934 Hall was forced to resign his chair in Rangoon and return to England due to his family having developed trachoma, which made it impossible for them to remain in the tropics.
Hall left Caterham in 1949 when he was appointed chair of the History of South East Asia department at the University of London School of Oriental and African Studies.