Born in July 1821, Daniel Harvey Hill grew up in ""genteel poverty"" on a large plantation in York District, South Carolina. He entered West Point and graduated in the middle of the renowned Class of 1842. Following garrison duty as a junior lieutenant with the First and Third Artilleries, Hill joined the Fourth Artillery at Fortress Monroe in January 1846. Six months later he was en route to Mexico. Published here for the first time, Hill's diary vividly recounts the Mexican War experiences of this proud young officer. He was observant and opinionated, recording details about soldiers, officers, logistics, units, the health of the army, and the progress of the campaign. Hill, who later took up the Confederate cause and earned the sobriquet ""Lee's Maverick General,"" emerged from the Mexican conflict an authentic hero, winning brevet promotions to captain and major for gallant conduct at Contreras (Padierna) and Chapultepec. Young lieutenant Hill came of age in Mexico, and there he encountered firsthand a different culture and witnessed in horror helpless civilians and their treasures washed away in the boiling stream of violence that was war. Hill's fascinating diary recounts these and other experiences in trenchant detail. The efforts of editors Hughes and Johnson have resulted in a valuable addition to the sources available to researchers and scholars of the U.S.-Mexican War.