Iakovos "Yiakoumakis" Tombazis was a merchant and ship-owner from the Greek island of Hydra who became the first admiral of the Greek Navy during the War of Independence against the Ottoman Empire (1821 - 1829).
Tombazis' date of birth is not known but 1782 is a possibility. As a businessman, he was shrewd and was the first to build greenhouses in Greece. In 1818 he was initiated into the Friendly Society (Filiki Eteria) which was preparing the ground for the revolt. When the War broke out, his fellow islanders made him admiral of their fleet. He took part in several clashes against the Turkish Navy in the eastern Aegean and soon realised that the Greek warships were not suited for conventional warfare. He proposed the use of fireships instead and sent Dimitris Papanikolis to burn the Turkish frigate "Moving Mountain" anchored at Eresos in Lesbos.
After Tombazis withdrew from the admiralty, he continued to support the revolution with his ships and money.