It had to, after losing the Mexican-American War (1846-1848).
1848.
Arizona, California, Nevada, Utah and New Mexico.
The Oregon Country was explored and claimed by various nations in the early 19th century, while Texas declared independence from Mexico in 1836 and became a Republic. The land ceded by Mexico to the United States came after the Mexican-American War, formalized in the Treaty of Guadalupe Hidalgo in 1848. Therefore, the Oregon Country was claimed first, followed by Texas, and then the land ceded by Mexico.
California and New Mexico.
The issue of slavery in the territory ceded by Mexico was decided by the Compromise of 1850, which allowed residents to determine whether to allow slavery through popular sovereignty. This meant that the territories of New Mexico and California could decide on the slavery issue for themselves when applying for statehood.
California, Arizona, New Mexico,Texas, Nevada, Utah, and parts of Colorado and Wyoming.
Mexico did, after the Mexican-American War (1846-1848).
The Mexican States of Alta California and Nuevo Mexico.
Not at all. The territories won over from Mexico were present-day California, Nevada, Utah, and parts of Colorado, Arizona, New Mexico, and Wyoming.
The Wilmot Proviso is the answer
After the war with Spain, Puerto Rico, Cuba, Phillipines and Guam were ceded to the U.S. under the treaty. The war with Mexico was different which ceded land to the U.S. from the Rio Grande as part of the treaty.
None. All territories Mexico ceded to the United States were already lost by that date. See related questions.