
Fillmore was born into relative poverty in the Finger Lakes area of New York state. His parents were tenant farmers during his early years and as a child he worked as an apprentice cloth maker, a job he hated. Though he had little formal schooling, he studied hard and became a successful attorney. He became a prominent Buffalo area attorney and politician, and in 1828 he was elected to the New York State Assembly. Four years later, in 1832 he was elected to the U.S. House of Representatives as a member of the Anti-Masonic Party. He became a Whig when the party formed in the mid-1830s. He even challenged editor Thurlow Weed for the state party leadership.
Through his career, Fillmore said that he personally considered slavery as an evil, but also believed that getting rid of it was beyond the powers of the federal government. Another rival New York Whig, William H. Seward, was also opposed to slavery, but unlike Fillmore, Seward argued that the federal government had had the power to end it.
Fillmore ran unsuccessfully for Speaker of the House when the Whigs took control of the chamber in 1841. He was made Chairman of the powerful Ways and Means Committee. He ran for and lost his bid to become the Whig Party's candidate for vice president in 1844, and also for New York governor the same year. Three years later, Fillmore was elected Comptroller of New York in 1847, the first to hold that post by direct election.
In spite of his loss in the race for Governor of his state, Fillmore received the Whig vice presidential nomination in 1848 as Zachary Taylor's running mate. The two won the election. But Fillmore was largely ignored by Taylor, even in the dispensing of patronage in New York. Much to Fillmore's dismay, Taylor consulted Weed and Seward instead.
As vice president, Fillmore presided over a number of very contentious debates in the Senate. Congress was deciding whether to allow slavery in the territories acquired as a result of the Mexican War. President Taylor did not support the expansion of slavery despite owning slaves himself. Fillmore supported Henry Clay's Omnibus Bill (which formed the basis of the 1850 Compromise). Taylor did not. Fillmore had the ability to cast the deciding vote in the Senate if there was a tie, while Taylor had the veto. But the conflict between the two men on the issue never came to a head. President Taylor died in July of 1850.
After he was sworn in as President, Fillmore dismissed the cabinet and changed the administration's policy. The new president used the power of his office to lobby for the passage of the Compromise, which he believed would be beneficial to both North and South. By that September, the Compromise of 1850 had become law. The most controversial part of it was the Fugitive Slave Act, which made it the law to compel free states to bring about the return of escaped slaves to those who claimed ownership of them. Fillmore felt duty-bound to enforce it. This damaged his popularity and also the Whig Party. Rather than uniting the nation, the Compromise only seemed to increase tensions between the North and South.
In foreign policy, Fillmore supported U.S. Navy expeditions to open trade with Japan. He opposed French designs on Hawaii. He also was opposed to Narciso López's filibuster expeditions to Cuba.
Fillmore wanted to run for President for a full term in 1852, but instead the Whigs picked General Winfield Scott as their candidate. The Whigs lost the election and the Party broke up after Fillmore's presidency. Many who belonged to Fillmore's conservative wing joined the "Know Nothings, formally known as the American Party. They were a populist party opposed to immigrants and Catholics, which was ironic because Fillmore's daughter was educated in a Catholic school. In his 1856 candidacy as that party's nominee, Fillmore avoided the subject of immigration. Instead he saw the key issue as the preservation of the Union. He won in only one state: Maryland.
In retirement, Fillmore was active in many civic endeavors—he helped in founding the University of Buffalo and served as its first chancellor. During the Civil War, Fillmore spoke out against secession. He agreed that the Union would have to be maintained by force if necessary, but he was also critical of the war policies of Abraham Lincoln. After peace was restored, he supported the Reconstruction policies of President Andrew Johnson. Fillmore enjoyed relatively good health for most of the remainder of his life, but he suffered a stroke in February 1874. He died after a second one on March 8. Two days later, he was buried at Forest Lawn Cemetery in Buffalo.
Fillmore's biographer Robert Scarry once wrote "No president of the United States has suffered as much ridicule as Millard Fillmore". According to Scarry, this is because of a tendency to lump all the presidents who served in the years just prior to the Civil War together into a group that is considered to be lacking in leadership. President Harry S. Truman characterized Fillmore as "a weak, trivial thumb-twaddler who would do nothing to offend anyone". Truman considered Fillmore to be partly responsible for creating the conditions that led to the war. Another Fillmore biographer, Paul Finkelman, has also written disparagingly about his subject, commenting that "on the central issues of the age his vision was myopic and his legacy is worse. In the end, Fillmore was always on the wrong side of the great moral and political issues".
Not all assessments are this negative. Biographer Robert Rayback praised Fillmore for "the warmth and wisdom with which he had defended the Union". Elbert B. Smith described Fillmore as "a conscientious president who chose to honor his oath of office and enforce the Fugitive Slave Act, rather than govern based on his personal preferences." According to Smith, his enforcement of the act gave Fillmore an undeserved pro-southern reputation. He added that Fillmore's place in history has also suffered because "even those who give him high marks for his support of the compromise have done so almost grudgingly, probably because of his Know-Nothing candidacy in 1856". Smith argued that Fillmore's association with the Know Nothings looks far worse in hindsight than it did at the time, and that for Fillmore, nativism was not the motive for his candidacy.
Fillmore, his biographers say, does not get enough credit for his work in international affairs. His administration resolved a dispute with Portugal left over from the Taylor administration, as well as a disagreement with Peru over the Guano Islands. His administration also peacefully resolved disputes with Britain, France, and Spain over Cuba.
Millard Fillmore, along with his wife Abigail, established the first real White House library. Today his home in East Aurora, New York still stands, and other sites have been preserved to honor him at his birthplace and boyhood home, where a replica log cabin was dedicated in 1963 by the Millard Fillmore Memorial Association. His statue stands outside Buffalo City Hall. At the university he helped found, the Millard Fillmore Academic Center and Millard Fillmore College both bear his name. Every year on his birthday, a ceremony is held by his grave site as a remembrance of his life.

Any assessment of Fillmore should be tempered with a consideration of the times in which he lived. The Whigs were not united enough to survive the divisions they experienced over the issue of slavery. When Fillmore sided with proslavery elements in ordering enforcement of the Fugitive Slave Law, he signed the death warrant of the Whig President. Eight years later, the election of the first Republican President would guarantee civil war. Fillmore was powerless to stop the momentum of the course that his nation was headed on.