French naval officer who was an early advocate of armour for naval vessels.

Hamelin's naval career began in 1806 when he served as shipboy aboard the frigate Vénus, commanded by his uncle, Baron Jacques-Félix-Emmanuel Hamelin. He later took part in the expedition to Spain in 1823 and distinguished himself in the action at Algiers in 1830. In the later years of Louis-Philippe's monarchy, Hamelin held a command in the Pacific. Having become vice admiral in 1848, he led the Black Sea squadron in the Crimean War, collaborating with the English admiral J.W.D. Dundas in the bombardment of Sevastopol (Sevastopol, Siege of). He became an admiral in 1854 and was minister of the navy from 1855 to 1860. Hamelin was an able administrator and took a notable part in developing the use of armour; the Gloire, launched in 1859, set the model for seagoing ironclads. When Napoleon III made his first concession to the Liberal opposition, Admiral Hamelin was among the first ministers to be dismissed. He held no further command but served as grand chancellor of the Legion of Honor until his death.