Claimed by France as part of the Louisiana Territory in 1682, Missouri had only a few small river towns by the start of the 19th century when the land passed to American hands and Lewis and Clark pushed up the Missouri River. Missouri was admitted to the Union as a slave state in 1821, per the Missouri Compromise (which permitted slavery in Missouri but prohibited it in any other part of the Louisiana Territory above the 36°30´ parallel), but abolitionists never compromised their ideals and bitter feelings were stoked along the Missouri–Kansas border by Civil War time.
The state’s ‘Show-Me’ nickname is attributed to Congressman Willard Duncan Vandiver, who said in an 1899 speech, ‘I come from a state that raises corn and cotton and cockleburs and Democrats, and frothy eloquence neither convinces nor satisfies me. I am from Missouri. You have got to show me.’ The name now implies a stalwart, not-easily-impressed character.