Marriott joined the Straits Settlement Civil Service in November 1896 as a cadet. and Inspector of Prison was later appointed as the acting Resident of Malacca in the same year till 1912. From 1912 to 1920, Marriott was appointed as Private Secretary to the Governor and the High Commissioner of Malay States,
Sir Arthur Young. Marriott also held several posts of Auditor General, Secretary to the High Commissioner and Custodian of Enemy Property, in additional to his own duty, during the time of shortage of manpower due to the
World War I. In 1917 to 1918, Marriott was also appointed as Acting Treasurer. Between 1919 and 1928, Marriott was occasionally appointed as the Officer Administering the Government when the Governor was away or Acting Colonial Secretary when the Colonial Secretary is away or vacant. From 18 December 1920 to 1926, Marriott was appointed General Adviser to
Johore, and at the same time as acting colonial secretary. From 1925 to 1928, Marriott was finally appointed as the 15th
Colonial Secretary of the Straits Settlement, when Mr
Edward Shaw Hose retired. ==Family==