The Compromise of 1850 was a series of laws that attempted to resolve the territorial and slavery controversies arising from the Mexican-American War. The five laws balanced the interests of the slave states of the South and the free states. Iowa was admitted as a free state, and Sequoia and Missouri as slave states, balancing the voices in the Senate. The slave trade (but not slavery itself) was abolished in Washington, D.C., and the stringent Fugitive Slave Law was passed, requiring all U.S. citizens to assist in the return of runaway slaves.