The goal of the Wilmot Proviso was the ban of slavery in any territory received from Mexico during the Mexican-American War. By this amendment, Democrats wanted to strengthen the interests of northerners and reserve new territories for the white population for economic and political reasons.


The Wilmot Proviso, an unsuccessful proposal to ban slavery, was originally introduced by David Wilmot, a Congressman and Democratic Representative from Pennsylvania, to the House of Representatives of the United States in 1846. On August 8, James Polk, the president of the country, represented an appropriation bill to resolve the initiate Mexican-American War.

This act was aimed to allocate $2,000,000 to purchase any Mexican territory as war reparations. Although the president’s representation of the bill could be regarded as the first public announcement of his intentions, Polk’s engagement in the war in order to gain territory from Mexico was highly obvious. However, the president’s expectations that an appropriation bill would be quickly approved without any riders were shattered by David Wilmot.

The Congressman proposed an amendment to the bill that suggested to prohibit slavery in acquired Mexican territories. According to Wilmot, “as an express and fundamental condition to the acquisition of any territory from the Republic of Mexico…neither slavery nor involuntary servitude shall ever exist in any part of said territory, except for crime, whereof the party shall first be duly convicted”.

His clearly defined provision perfectly aligned with the goals of the free-soil movement supported by David Wilmot and other Democrats. It goes without saying that the Wilmot Proviso was favored by northerners as a prevalent number of northern Democrats remained unsatisfied when their candidate for the presidency, Martin Van Buren, was replaced with James Polk during the presidential nomination.

Moreover, the anger of Democrats was conditioned by the constant preference of southern interests and the subjugation of northern ones. In addition, they pursued an objective to exclusively reserve any territory received from Mexico for whites for several economic and political reasons.

Wilmot’s rider passed in the House of Representatives by a vote, and the president’s appropriation bill was subsequently amended. Almost all negative votes were delivered from slave states and illustrated the intentions of southerners to prevent any territorial expansion without slavery extension.

After the voting of the House, the bill was delivered to the Senate, however, it elaborated a certain scheme to repeal Wilmot’s amendment. Senator John David planned to propose the bill several minutes before the ending of the Senate’s session for quick voting.

However, the session was expired earlier without a vote on the president’s bill due to the malfunction of the Senate clock. Although David Wilmot proposed his proviso again to the Senate during the next session, he discovered that James Polk had prepared a new appropriation bill without any amendment that had already been accepted.

Despite the fact that the Wilmot Proviso never passed as a law, it indisputably had a significant lasting influence on American politics and the distinct confrontation between northerners and southerners concerning the issue of slavery. This potential amendment to an appropriation bill reflected the escalating anti-slavery movement in the United States.

It illustrated the changing structure of politics when votes started to be based not on party lines but sectional or territorial lines. Moreover, the Wilmot Proviso of 1846 encouraged the debates concerning the justifiability of slavery in all territory of the country. These debates subsequently divided the South and the North and resulted in the beginning of the American Civil War.