In 1838 Redhouse returned to work for the Ottoman government as an interpreter to the Grand Vizier and the Minister for Foreign Affairs. He transferred to the Ottoman Admiralty in 1840, became a member of the Naval Council, and went to Syria to help communications between the English Austrian and Ottoman fleets which were running a blockade. He received the Sultan's Imperial Order (İftihar Nişanı) in 1841. In 1843 he was appointed secretary and interpreter to the British Commissioner William Fenwick Williams, who was arranging a peace treaty between the Ottoman Empire and Persia. Redhouse was also involved in peace negotiations at Erzurum in 1847 and was awarded the Persian Order of the Lion and the Sun. He returned to Constantinople until 1853. He was appointed oriental translator to the Foreign Office in 1854 and went to Paris to help negotiate a treaty with Persia.
