Complex sentence: Dubois left India in January 1823, with a special pension conferred on him by the East India Company, and on reaching Paris was appointed director of the Missions Étrangères, of which he afterwards became superior (1836-1839).
Split into simpler sentences: Dubois left India in January 1823, with a special pension conferred on him by the East India Company. On reaching Paris, he was appointed director of the Missions Étrangères, of which he afterwards became superior (1836-1839).