During the mid-1800s, many prominent Americans saw manifest destiny as a necessary and beneficial expansion of their political institutions and social values. Manifest Destiny led people to venture west and settle new lands, but the controversial slave issue also reached the new territories. A rift was created between the pro-slavery and anti-slavery factions that linked to the sectional conflict. Dispute over slavery and freemen in the North and South led to the Missouri Compromise. The Compromise of 1850 is another example of sectionalism in which the United States admitted California as a free state, while Utah and New Mexico were left without restrictions on slavery. A third example is the Kansas-Nebraska Act by which Congress decided to leave Kansas and Nebraska open to popular sovereignty on the issue of slavery. The conflict over slavery introduced sectional disputes, as the nation pursued what it called its manifest destiny, which, in turn, became a significant cause of the Civil War. Manifest destiny is the idea that Americans were destined to settle the new territories and connecting the Atlantic and Pacific oceans. It was the belief that God supported American westward expansion, adding to the Louisiana Purchase of 1803 which, under President Jefferson, had doubled the size of the United States. A journalist named John L. O'Sullivan wrote an article in 1839, through which he coined the term manifest destiny and predicted a divine destiny for the United States. This fate not only has to do with westward expansion, but each state would also share the same values. In 1820, pro-slavery and anti-slavery factions in the United States Congress passed the Missouri Compromise, in w...... .. middle of paper ......and new territories, and these debates led to a sectoral crisis between states. The Missouri Compromise was the beginning of debates over slavery in the new territories. The Kansas-Nebraska Act led to further extending sectionalism by allowing popular sovereignty to choose whether or not a state had slavery. The Compromise of 1850 spread the idea of ​​popular sovereignty over more territories, while increasing sectionalism and conflict within congress. In the 1850s there was great tension between the states. In 1860, Lincoln, a Republican, was elected. The South feared the ideals of the Republicans and also feared what Lincoln would do to the Southern states. The South went to war with the North over slavery. Manifest Destiny added to existing sectoral crises by introducing the problems of slavery into the new territories, thus leading the country to war.