Additionally, the Missouri Compromise stated that the admission of new states had to follow a 1:1 ratio; this was done to maintain the balance of power within the Senate between slave and free states. However, the new lands acquired under the Mexican Cession did not fall under the Missouri ...
Mexican-American War, war between the U.S. and Mexico from 1846 to 1848. It was caused by a territorial dispute stemming from the United States’ annexation of Texas in 1845 and from contention over whether Texas ended at the Nueces River or the Rio Gran