War Hawk, in U.S. history, any of the expansionists primarily composed of young Southerners and Westerners elected to the U.S. Congress in 1810, whose territorial ambitions in the Northwest and Florida inspired them to agitate for war with Great Britain. The War Hawks, who included such future political leaders as Henry Clay and John C. Calhoun, fiercely and aggressively resented American economic injuries and national humiliation during the Napoleonic Wars. They were further indignant over British encouragement of Indian hostilities toward settlers in the Northwest and hoped to use war with England to wrest Florida from Spain, Britain’s ally. The nationalistic fervour and anti-British sentiment whipped up by the War Hawks was a contributing cause to the War of 1812.