The 1846 Wilmot Proviso was a bold attempt by opponents of slavery to prevent its introduction in the territories purchased from Mexico following the Mexican War. Named after its sponsor, Democratic representative DAVID WILMOT of Pennsylvania, the proviso never passed both houses of Congress, but it did ignite an intense national debate over slavery that led to the creation of the antislavery REPUBLICAN PARTY in 1854.
The Mexican War of 1845–1846 was fueled, in part, by the desire of the United States to annex Texas. President JAMES POLK asked Congress in August 1846 for $2 million to help him negotiate peace and settle the boundary with Mexico. Polk sought the acquisition of Texas and other Mexican territories. Wilmot quickly offered his proposal, known as the Wilmot Proviso, which he attached to President Polk's funding measure. The proviso would have prohibited slavery in the new territories acquired from Mexico, including California.
The proviso injected the controversial slavery issue into the funding debate, but the House approved the bill and sent it to the Senate for action. The Senate, however, adjourned before discussing the issue.
When the next Congress convened, a new appropriations bill for $3 million was presented, but the Wilmot Proviso was again attached to the measure. The House passed the bill and the Senate was forced to consider the proposal. Under the leadership of Senator JOHN C. CALHOUN of South Carolina and other proslavery senators, the Senate refused to accept the Wilmot amendment, approving the funds for negotiations without the proviso.
For several years, the Wilmot Proviso was offered as an amendment to many bills, but it was never approved by the Senate. However, the repeated introduction of the proviso kept the issue of slavery before the Congress and the nation. The COMPROMISE OF 1850, which admitted California as a free state but left the issue of slavery up to the citizens of New Mexico and Utah, created dissension within the Democratic and Whig parties. The strengthening of federal enforcement of the FUGITIVE SLAVE ACT (9 Stat. 462) angered many northerners and led to growing sectional conflict.
The creation of the Republican Party in 1854 was based on an antislavery platform that endorsed the Wilmot Proviso. The prohibition of slavery in any new territories became a party tenet, with Wilmot himself emerging as Republican Party leader. The Wilmot Proviso, while unsuccessful as a congressional amendment, proved to be a battle cry for opponents of slavery.
Fehrenbacher, Don Edward. 1995. Sectional Crisis and Southern Constitutionalism. Baton Rouge: Louisiana State Univ. Press.
Morrison, Chaplain W. 1967. Democratic Politics and Sectionalism: The Wilmot Proviso Controversy. Chapel Hill: Univ. of North Carolina Press.
Rayback, Joseph G. 1971. Free Soil: The Election of 1848. Lexington: Univ. Press of Kentucky.