Born in 1835 in Portadown, Robert Hart was the eldest of twelve children. The Harts had a background in distilling, shop-keeping and farming. They settled in Ravernet outside Lisburn.
Robert Hart was 15 years old when he came to Queen's College, Belfast in 1850. He graduated with a Bachelor of Arts in 1853. He was the only candidate awarded a graduate scholarship (valued at £40) in Modern Languages.
In 1854 the British Foreign Secretary, the Earl of Clarendon, put in place a scheme for the development of the consular service in China and Japan. A circular was sent to the Queen's Colleges in Ireland - Galway, Dublin, Belfast and Cork - requesting recommendations. Robert Hart put his name forward, along with 36 other candidates, and was nominated by the College Council; he was then appointed to the post of Supernumeracy Inspector in China. He was 19 years old.
Very little was known about China in 1854; British Consular staff in Hong Kong and the Treaty Ports were responsible for promoting Britain's trading interests in China. Trade continued to grow and with this expansion the need for interpreters.
Robert Hart spent short periods of time in Hong Kong, Ningpo and the Canton as an interpreter. In 1859 Hart resigned from the British Consular Service; the Canton Viceroy asked him to join the Chinese Imperial Maritime Service, which at that time had been established for only four years.
Robert Hart was appointed Inspector General of the Chinese Imperial Maritime Customs in 1863. He was responsible to the Chinese Government for the operating of the Customs Service. His post was a delicate balance of organisational skill and diplomacy and he had considerable influence over American and European authorities.
By the end of the 19th century the Customs Service was responsible for the Chinese Imperial Postal Service, port development, inland and coastal waterways as well as collecting revenue. Robert Hart was made a Baronet in 1893 in recognition of his achievements in China. China showered distinction after distinction upon him, including the Order of the Double Dragon, the Rank of the First Class for Three Generations of the Peacocks's Feather and rarest of all, posthumously, the title of the Senior Guardian of the Heir Apparent. He left his post at the Inspectorate in 1908 and returned to England; he was Pro-Chancellor of Queen's University, Belfast from 1908 until his death in 1911.