united states general who was a hero of the war of 1812 and who defeated santa anna in the mexican war. was a united states army general, diplomat, and presidential candidate. known as "old fuss and feathers" and the "grand old man of the army", he served on active duty as a general longer than any other man in american history and most historians rate him the ablest american commander of his time. over the course of his fifty-year career, he commanded forces in the war of 1812, the mexican-american war, the black hawk war, the second seminole war, and, briefly, the american civil war, conceiving the union strategy known as the anaconda plan that would be used to defeat the confederacy. forestalled the civil war by instating the fugitive slave act , banning slave trade in dc, admitting california as a free state, splitting up the texas territory, and instating popular sovereignty in the mexican cession. By Henry Clay. series of legislation addressing slavery and the boundaries of territories acquired during the mexican-american war. california was admitted as a free state, texas received financial compensation for relinquishing claim to lands west of the rio grande river, the territory of new mexico was organized with popular sovereignty, the slave trade was abolished in washington, d.c., and the fugitive slave law was passed it temporarily defused sectional tensions in the united states, postponing the secession crisis and the american civil war. also repealed the compromise of 1820.