The United States’ territorial expansion inadvertently contributed to the eradication of the institutionalization of slavery. The gradual process of Westward expansion amplified the economic and political rift between White Northerners and Southerners. Following the Revolutionary War, white Northerners and Southerners alike were content with their respective economic systems. However, the seemingly perpetual acquisitions of territories repeatedly ignited a national debate; with each region interested in protecting their economical and political systems respectively.
The United States first expanded with The Northwest Ordinance of 1787. The Northwest Ordinance established the Northwest Territory—the states of Illinois, Indiana, Michigan, Ohio, and Wisconsin. More importantly, this legislation outlawed slavery north of the Ohio River.
In 1803, the United States acquired the Louisiana Purchase—ironically, as a direct result of a slave revolt in Haiti—from France. The Louisiana Purchase would spark the first national political debate. As settlers began to move into the Louisiana territory, the issue of slavery arose. A territory could apply for statehood after it reached 60,000 settlers. In 1819, Missouri applied for statehood, entering the Union as a slave state. This enraged White Northerners. The admittance of Missouri gave the slave holding states the majority in the Senate; foreshadowing, that future political policies, would favor the Southern economic system—slavery. In an effort to consolidate the North and South, Henry Clay a representative from Kentucky constructed the Missouri Compromise. This allowed Missouri to enter the Union as a slave state, in addition to, Maine entering the Union as a free state. This temporarily moderated the geographical dispute.
In, 1846 the United States began its war with Mexico. Amidst the war, a Pennsylvania