As the ink was drying on the Constitution of the United States, the northern states were immersed in ridding their books of laws institutionalizing slavery. It was felt that slavery would "die on the vine" as the movement swept south, but by 1820 slavery was not only alive, but growing in the South.
Slowly, the North gained power in the U. S. House of Representatives, where the population determined the number of representatives each state received. The Louisiana Purchase represented a problem for Congress. With the purchase the slave state/free state balance would be thrown off in the future as the land was carved into states. Congress banned slavery in the purchased lands north of 36 degrees 30 minutes with the exception of Missouri in the Compromise of 1820. The increasingly lopsided Free State/Slave State representation led the House to implement a "gag rule" prohibiting abolitionist petitions reaching the House floor. In 1844 the gag rule was lifted.
Afraid of Whig charges that the War with Mexico was being fought to extend slavery, some Democratic House members felt it was time to ban slavery in the territories to be acquired. Others felt it was simply time to give back to James Polk what he had been dishing out. In the Election of 1844 Polk defeated Martin Van Buren for the Democratic presidential nomination. He then gave patronage jobs in New York to the anti-Van Buren faction in the state, alienating Preston King and others. In 1846, David Wilmot was upset by last minute changes in the Walker Tariff. Hannibal Hamlin and many northern Whigs were simply against slavery.
James Polk wanted to end the Mexican American War as quickly as possible and when the opportunity arose, he needed money to compensate Mexico for the land it was going to lose. He decided to present a $2,000,000 appropriation bill (known as the "Two Million Dollar Bill") on a Saturday when the House was in committee, hoping to push the bill through the House quickly. It passed, on that day, from the Democrat-controlled Ways and Means Committee to the Committee of the Whole.
When the "Two Million Dollar Bill" reached the Committee of the Whole, Judge Jacob Brinkerhoff quietly wrote up the Proviso, basing it on his memory of the wording of the the Northwest Ordinances of 1787, written by Thomas Jefferson. He then showed the paper to Whig leader Samuel Vinton of Ohio. Vinton asked Brinkerhoff if the Democrats would support it and Brinkerhoff said some would.
A group of anti-slavery Democrats including Hannibal Hamlin, Preston King, George Rathbun and others were excitedly whispering on the floor of the House when Brinkerhoff approached. The group was discussing proposed wording of an anti-slavery amendment to the appropriations bill when Brinkerhoff showed them his Proviso. Hamlin immediately liked it because the Judge's was the shortest. All agreed it should be proposed as an amendment immediately.
The Committee of the Whole is structured under strict parliamentary rules and Brinkerhoff, who was known to be an anti-slavery Democrat, did not think he would be recognized by the chair. At 33 and serving his first term in the House, Democrat David Wilmot was a popular member from Pennsylvania whose anti-slavery views were not known at the time and he was liked by many Southerners. The Proviso supporters felt Wilmot had the best chance of being recognized by the chair. Their plan was simple: All would seek the recognition of the chair and if any one of them got the floor, they would turn it over to the Representative from Pennsylvania. There was no need for such an elaborate plan. The chair recognized Wilmot following a speech by Kentucky Whig Henry Grider.
While in front of the Committee of the Whole, Wilmot spoke to the members present:
...an express and fundamental condition to the acquisition of any territory from Mexico, that neither slavery or involuntary servitude should ever exist therein.
Wilmot then moved that the Proviso be added to the first section of the "Two Million Dollar Bill."
Immediately after Wilmot spoke, Washington Hunt of N. Y. spoke against both the bill and slavery, supporting Wilmot while opposing the bill. Alexander Dromgoole Sims of South Carolina then spoke, becoming the first member to attack Wilmot's proposal.
The Committee of the Whole passed the bill as amended 83 to 64. Within the hour a vote on the Two Million Dollar Bill was held in front of the full House, passing 85 to 79 according to the Congressional Record. The only slave state members to vote for the Proviso were Grider and William P. Tomasson of Kentucky. Only 3 representatives from free states voting against adding the Proviso: Orlando Ficklin, future Union general John A. McClernand and Stephen A. Douglas. It was the first time a vote broke along regional lines (North and South), not the traditional party lines.
To avoid voting on the first appropriations bill, the Senate delayed debate. On the final day of the Senate session, John Davis of Massachusetts rose to speak on the bill. He continued until the Senate session ended. Since bills don't carry over between sessions, this effectively killed the bill.
During 1846 only news on the War with Mexico overshadowed the discussion of the Wilmot Proviso and the 1846 elections. When the new Congress convened it would be under Whig control. Polk's team in the House, mostly pro-slavery Democrats, submitted the "Three Million Dollar Bill." During debate of the bill, on February 13, 1847, John Quincy Adams was carried sick from the floor of the House.
As the Three Million Dollar Bill moved to the floor, Brinkerhoff, Hamlin and the others began looking for Wilmot to again submit the Proviso. He was not on the floor, and as far as they could tell, he was not in building. In a parliamentary move, William Dromgoole, Representative of Virginia and a supporter of Polk, claimed the time was up and tried to move the bill to a vote. When overruled by the chair, Dromgoole raised a question of order. "The Wilmot Proviso is an arrogant assumption of power..." referring to the belief that the House could not restrict slavery because it was a Constitutional question.
As Hamlin, Brinkerhoff and others scrambled to find Wilmot, Preston King rose to offer the Proviso. Immediately, the Committee of the Whole broke into a general furor. John McClernand insisted he had the floor. He was overruled, but he appealed the decision to the chair. During the resulting melee, the Proviso forces met and turned the amendment over to Hamlin to propose, which he did after order was restored. Still, young Wilmot was no where to be found. Finally, a vote was called in the House. Wilmot, appearing just before his name was called, responded "Aye," voting to add the amendment to the bill.
As the pro-Proviso forces gathered around Wilmot to find out what happened, Wilmot told of being summoned to the White House by James Polk himself. When Polk was finished Wilmot "hastened" to the Capital in time to enter his vote. For the rest of his life Wilmot believed that Polk had detained him specifically with the hope of defeating the measure.
In the Senate, the Three Million Dollar Bill was passed without the Wilmot Proviso in it and returned to the Joint Committee. The bill would be returned to the House, where it would be passed without the Proviso.
Abolitionist gains in power once again moved the United States to the brink of war in the late 1840's. Southerners felt the Missouri Compromise covered all land west of the Mississippi River, while northerners took the compromise at face value...only the lands in the Louisiana Purchase were covered by the Compromise. The Wilmot Proviso had a chilling affect on North-South relations because it indicated that anti-slavery forces would never be happy with status quo.
Beginning with the Wilmot Proviso, from 1846 on a disturbing trend split America not along party lines, but along regional lines. Although initially only a few votes were of a regional nature, and the number reduced in the early 1850's, by 1857 regional votes were more common.
Wilmot Proviso (1846 version)
Provided that, as an express and fundamental condition to the acquisition of any territory from the Republic of Mexico by the United States, by virtue of any treaty which may be negotiated between them, and to the use by the Executive of the moneys herein appropriated, 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.
Wilmot Proviso (1847 version)
There shall be neither slavery, nor involuntary servitude in any territory on the continent of America which shall hereafter be acquired by or annexed to the United States by virtue of this appropriation (the $3,000,000) on in any other manner whatever, except for crime whereof the party shall have been duly convicted.
The text of the Wilmot Proviso was based on Jefferson text for the original Northwest Ordinance (Ordinance of 1784). It was later revised to become the Fourteenth Amendment
The text of the Proviso was written by Ohio Representative Judge Jacob Brinkerhoff and not David Wilmot, for whom the Proviso is named. A popular Pennsylvania Representative, Wilmot would be tapped to present the amendment because he would probably be recognised by the chair.