Compromise 2: Missouri, Slave Or Free?


Monroe, Clay, and Senate leaders worked behind the scenes to devise a compromise and break the deadlock. It would center on what is now the state of Maine, which had been part of Massachusetts since colonial times. In June 1819 the Massachusetts legislature consented to separate statehood for what had been its northern “district.” The Senate leadership promptly joined the two admissions into a single bill, which if passed would preserve the concise balance of sections in the Senate.

But the Northern majority in the House remained determined to enforce gradual emancipation, making a further concession necessary. So Sen. Jesse Thomas of Illinois, who had been voting with the proslavery side, proposed that slavery should be prohibited not in Missouri but in all the rest of the Louisiana Purchase lying north of 36 degrees and 30 minutes of latitude, that is, the southern boundary of Missouri. This would seriously restrict the expansion of slavery, even if not into the land originally in question.

The Thomas proviso passed the House with the support of 95 out of 100 Northern representatives, and even the Southern members supported it, 39 to 37. It is remarkable how many of the Southern congressmen of 1820 were willing to prohibit slavery in what was then the greater part of the territories. Given the Thomas proviso, 18 Northern representatives then either voted for Missouri statehood without restrictions on slavery or else abstained—enough for it to pass with the support of a solid South. In the Senate all the compromise measures were voted on together as a package: the South voted 20 to 2 in favor; the North, 18 to 4 against.

Although most Northern congressmen at the time would have preferred Tallmadge’s policy of gradual emancipation, in practice the Missouri Compromise helped stabilize sectional competition for 34 years. Its repeal in 1854 by the Kansas-Nebraska Act, which revived the specter of slavery’s extension westward, constituted a monumental legislative blunder. The Northern public had counted on the Thomas proviso of the Missouri Compromise to hold the Great Plains safe for family farms and keep out slave-operated plantations. Abraham Lincoln, who had reconciled himself to private law practice, reentered politics to denounce the act. The new Republican Party that he would lead to victory six years later was born in reaction to what its members saw as the overreaching aggression of slavery expansionists. The Republicans reaffirmed the principle that had been maintained by the Missouri Compromise for more than a generation: congressional power to restrict the extension of slavery into new areas.