U.S. President John Tyler signs a constitutional resolution that allows Texas to join the Union.
U.S. Tries to Buy Land (Slidell and Polk)
Polk sends john Slidell to Mexico to try to buy New Mexico and California. When this news is leaked to the Mexican public, the Mexican President, fearing the public opinion is turning against him, refuses to meet with Slidell.
U.S. Troops Stationed at Disputed Border
Polk orders General Zachary Taylor to advance to the border at the Rio Grande disputed by Mexico and the U.S.
U.S. Declares War
Congress responds to a request from Polk, declaring war on Mexico. They hope this will intimidate Mexico into giving up the disputed part of Texas and selling California and New Mexico to them.
Battle of Monterey
Taylor's army invades Monterrey as part of a plan to cut off Northern Mexico. Taylor defeats the Mexican troops which helps convince more men to join the army.
Mexico City Surrendered
The US army occupies Mexico City which is surrendered to them.
Treaty of Guadalupe Hildago
Negotiators sign the peace treaty between Mexico and the U.S. and rush it to Washington, D.C.