Final answer:
The Missouri Compromise, Wilmot Proviso, and Compromise of 1850 all dealt with the issue of slavery in new U.S. territories, balancing between free and slave states and employing popular sovereignty.
Step-by-step explanation:
The Missouri Compromise, Wilmot Proviso, and Compromise of 1850 were legislative efforts concerned with the expansion of slavery into new territories of the United States. Each of these measures dealt, in different ways, with the divisive question of whether new territories should be free or slave-holding. This question was crucial in determining the balance of power between northern and southern states and was a major factor leading up to the American Civil War.
The Missouri Compromise of 1820 was an early attempt at keeping the balance between slave and free states. It admitted Missouri as a slave state and Maine as a free state, maintaining the Senate balance, while drawing a line across the country, the 36° 30' parallel north, north of which slavery was to be prohibited in future territories.
The Wilmot Proviso sought to entirely prohibit the expansion of slavery into territories acquired from Mexico. Although it passed in the House of Representatives, it repeatedly failed in the Senate due to sectional divides, with northern legislators supporting and southern legislators opposing the measure.
Finally, the Compromise of 1850 offered several provisions, including admitting California as a free state, defining a boundary for Texas, abolishing the slave trade in Washington, DC (although not slavery itself), and enacting a tougher Fugitive Slave Act, which was a concession to southern states. It also adopted the principle of 'popular sovereignty', allowing the residents of the Utah and New Mexico territories to decide the issue of slavery themselves.