Spink was commissioned as an ensign in the 12th Regiment of Foot on 2 September 1806. After seeing action in India between 1808 and 1809 during the Travancore Rebellion, he led an attack on an enemy position on the island of Réunion in the Indian Ocean in 1810 and then took part in the Invasion of Isle de France also in the Indian Ocean and subsequent march on its capital, Port Louis, in November 1810 during the Napoleonic Wars.