Martin Van Buren in the context of "Democratic-Republican Party"

The Free Soil Party, also called the Free Democratic Party or the Free Democracy, was a political party in the United States from 1848 to 1854, when it merged into the Republican Party. The party was focused on opposing the expansion of slavery into the western territories of the United States. The 1848 presidential election took place in the aftermath of the Mexican–American War and debates over the extension of slavery into the Mexican Cession. After the Whig Party and the Democratic Party nominated presidential candidates who were unwilling to rule out the extension of slavery into the Mexican Cession, anti-slavery Democrats and Whigs joined with members of the Liberty Party (an abolitionist political party) to form the new Free Soil Party. Running as the Free Soil presidential candidate, former President Martin Van Buren won 10.1 percent of the popular vote, the strongest popular vote performance by a third party up to that point in U.S. history.

Though Van Buren and many other Free Soil supporters rejoined the Democrats or the Whigs after the 1848 election, Free Soilers retained a presence in Congress over the next six years. Led by Salmon P. Chase of Ohio, John P. Hale of New Hampshire, and Charles Sumner of Massachusetts, the Free Soilers strongly opposed the Compromise of 1850, which temporarily settled the issue of slavery in the Mexican Cession. Hale ran as the party's presidential candidate in the 1852 presidential election, taking just under five percent of the vote. The 1854 Kansas–Nebraska Act repealed the long-standing Missouri Compromise and outraged many Northerners, contributing to the collapse of the Whigs and spurring the creation of a new, broad-based anti-slavery Republican Party. Most Free Soilers joined the Republican Party, which emerged as the dominant political party in the United States in the Third Party System (1856–1894).

Presidential elections were held in the United States on November 7, 1848. Held in the aftermath of the Mexican–American War, General Zachary Taylor of the Whig Party defeated Senator Lewis Cass of the Democratic Party.

Despite Taylor's unclear political affiliations and beliefs, and the Whig opposition to the Mexican–American War, the 1848 Whig National Convention nominated the popular general over party stalwarts such as Henry Clay and Daniel Webster. For vice president, the Whigs nominated Millard Fillmore, a New York Whig known for his moderate views on slavery. Incumbent President James K. Polk, a Democrat, honored his promise not to seek re-election, leaving his party's nomination open. The 1848 Democratic National Convention nominated Senator Lewis Cass of Michigan after former President Martin Van Buren withdrew his bid for a second term over a platform dispute. Van Buren broke from his party to lead the ticket of the Free Soil Party, which opposed the extension of slavery into the territories.

The Indian removal was the United States government's policy of ethnic cleansing through the forced displacement of self-governing tribes of American Indians from their ancestral homelands in the eastern United States to lands west of the Mississippi River—specifically, to a designated Indian Territory (roughly, present-day Oklahoma), which many scholars have labeled a genocide. The Indian Removal Act of 1830, the key law which authorized the removal of Native tribes, was signed into law by United States president Andrew Jackson on May 28, 1830. Although Jackson took a hard line on Indian removal, the law was primarily enforced during the Martin Van Buren administration, 1837 to 1841. After the enactment of the Act, approximately 60,000 members of the Cherokee, Muscogee (Creek), Seminole, Chickasaw, and Choctaw nations (including thousands of their black slaves) were forcibly removed from their ancestral homelands, with thousands dying during the Trail of Tears.

Indian removal, a popular policy among incoming settlers, was a consequence of actions first by the European colonists and then later on by the American settlers in the nation during the thirteen colonies and then after the revolution, in the United States of America also until the mid-20th century.

The Democratic Party is one of the two major political parties of the United States political system and the oldest active political party in the country. Founded in 1828, the Democratic Party is the oldest active voter-based political party in the world. The party has changed significantly during its nearly two centuries of existence. Once known as the party of the "common man", the early Democratic Party stood for individual rights and state sovereignty, and opposed banks and high tariffs. In the first decades of its existence, from 1832 to the mid-1850s (known as the Second Party System), under Presidents Andrew Jackson, Martin Van Buren, and James K. Polk, the Democrats usually defeated the opposition Whig Party by narrow margins.

Before the American Civil War, the party generally supported slavery or insisted it be left to the states. After the war until the 1940s, the party opposed civil rights reforms in order to retain the support of Southern white voters. The Republican Party was organized in the mid-1850s from the ruins of the Whig Party and Free Soil Democrats. It was dominant in presidential politics from 1860 to 1928. The Democrats elected only two Presidents during this period: Grover Cleveland (in 1884 and 1892) and Woodrow Wilson (in 1912 and 1916). Over the same period, the Democrats proved more competitive with the Republicans in Congressional politics, enjoying House of Representatives majorities (as in the 65th Congress) in 15 of the 36 Congresses elected owing largely to their dominance of the Solid South, although only in five of these they formed the majority in the Senate. Furthermore, the Democratic Party was split between the Bourbon Democrats, representing Eastern business interests, and the agrarian party elements representing poor farmers in the South and West. After the Republican landslide in the 1894 House elections, the agrarian element, marching behind the slogan of free silver (i.e. in favor of inflation), captured the party. They nominated William Jennings Bryan in the 1896, 1900, and 1908 presidential elections, although he lost every time. Both Bryan and Wilson were leaders of the progressive movement in the United States (1890s–1920s) and opposed imperialistic expansion abroad while sponsoring liberal reforms at home despite supporting racism and discrimination against blacks in government offices and elsewhere.

John Tyler (March 29, 1790 – January 18, 1862) was the tenth president of the United States, serving from 1841 to 1845, after briefly holding office as the tenth vice president in 1841. He was elected vice president on the 1840 Whig ticket with President William Henry Harrison, succeeding to the presidency following Harrison's death 31 days after assuming office. Tyler was a stalwart supporter and advocate of states' rights, including regarding slavery, and he adopted nationalistic policies as president only when they did not infringe on the states' powers. His unexpected rise to the presidency posed a threat to the presidential ambitions of Henry Clay and other Whig politicians and left Tyler estranged from both of the nation's major political parties at the time.

Tyler was born into a prominent slaveholding Virginia family. He became a national figure at a time of political upheaval. In the 1820s, the Democratic-Republican Party, at the time the nation's only political party, split into several factions. Initially a Jacksonian Democrat, Tyler opposed President Andrew Jackson during the nullification crisis as he saw Jackson's actions as infringing on states' rights and criticized Jackson's expansion of executive power during Jackson's veto on banks. This led Tyler to ally with the southern faction of the Whig Party. He served as a Virginia state legislator and governor, U.S. representative, and U.S. senator. Tyler was a regional Whig vice-presidential nominee in the 1836 presidential election, which Democrat Martin Van Buren won. He was the sole nominee on the 1840 Whig presidential ticket as William Henry Harrison's running mate. Under the campaign slogan "Tippecanoe and Tyler Too", the Harrison–Tyler ticket defeated Van Buren.

John Jordan Crittenden (September 10, 1787 – July 26, 1863) was an American statesman and politician from the U.S. state of Kentucky. He represented the state in the U.S. House of Representatives and the U.S. Senate and twice served as United States Attorney General in the administrations of William Henry Harrison, John Tyler, and Millard Fillmore. He was also the 17th governor of Kentucky and served in the state legislature. Although frequently mentioned as a potential candidate for the U.S. presidency, he never consented to run for the office.

During his early political career, Crittenden served in the Kentucky House of Representatives and was chosen as speaker on several occasions. With the advent of the Second Party System, he allied with the National Republican (later Whig) Party and was a fervent supporter of, and eventually a protege of Henry Clay and opponent of Democrats Andrew Jackson and Martin Van Buren.

Salmon Portland Chase (January 13, 1808 – May 7, 1873) was an American politician and jurist who served as the sixth chief justice of the United States from 1864 to his death in 1873. He earlier served as the 25th United States secretary of the treasury from 1861 to 1864, during the American Civil War in the Abraham Lincoln administration. Chase also served as the 23rd governor of Ohio from 1856 to 1860, and represented Ohio in the United States Senate from 1849 to 1855 and again in 1861. Chase is therefore one of the few American politicians who have held constitutional office in all three branches of the federal government, in addition to serving in the highest state-level office. From the 1850s onward, even as Chief Justice, Chase sought a presidential nomination that never came because he was considered inept.

Born in Cornish, New Hampshire, Chase studied law under Attorney General William Wirt before establishing a legal practice in Cincinnati. He became an anti-slavery activist and frequently defended fugitive slaves in court. Chase left the Whig Party in 1841 to become the leader of Ohio's Liberty Party. In 1848, he helped establish the Free Soil Party and recruited former President Martin Van Buren to serve as the party's presidential nominee. Chase won election to the Senate the following year, and he opposed the Compromise of 1850 and the Kansas–Nebraska Act. In the aftermath of the Kansas–Nebraska Act, Chase helped establish the Republican Party, which opposed the extension of slavery into the territories. After leaving the Senate, Chase served as the first Republican governor of Ohio from 1856 to 1860.

John Parker Hale (March 31, 1806 – November 19, 1873) was an American politician and lawyer from New Hampshire. He served in the United States House of Representatives from 1843 to 1845 and in the United States Senate from 1847 to 1853 and again from 1855 to 1865. He began his congressional career as a Democrat, but helped establish the anti-slavery Free Soil Party and eventually joined the Republican Party.

Born in Rochester, New Hampshire, Hale established a legal practice in Dover, New Hampshire after graduating from Bowdoin College. Hale won election to the New Hampshire House of Representatives in 1832 and served as the United States Attorney for New Hampshire under President Andrew Jackson and President Martin Van Buren. He won election to the United States House of Representatives in 1842 but was denied the party's nomination in 1844 due to his opposition to the annexation of Texas. After losing his seat, he continued to campaign against slavery and won election to the Senate in 1846 as an Independent Democrat. In the Senate, he strongly opposed the Mexican–American War and continued to speak against slavery.

Mathew B. Brady (c. May 18, 1822 – January 15, 1896) was an American photographer. Known as one of the earliest and most famous photographers in American history, he is best known for his scenes of the American Civil War. He studied under inventor Samuel Morse, who pioneered the daguerreotype technique in America. Brady opened his own studio in New York City in 1844, and went on to photograph U.S. presidents John Quincy Adams, Abraham Lincoln, Millard Fillmore, Martin Van Buren, and other public figures.

When the Civil War began, Brady's use of a mobile studio and darkroom enabled thousands of vivid battlefield photographs to bring home the reality of war to the public. He also photographed generals and politicians on both sides of the conflict, though most of these were taken by his assistants rather than by Brady himself.