Beside all the fight that had occurred on whether the war was in the right or in the wrong, the Americans had a huge success on the battlefield. Zachary Taylor and Winfield Scott had won a series of remarkable victories against the Mexican armies. This succession was in spit the fact that Mexicans had outnumbered the Americans. In September of 1847, after a handful of overland campaigns, American troops under Scott captured Mexico's capital, Mexico City, and the fightinghad stopped.
We win! Victory is ours! Now we can claim the south.
We are going to pay 15 million for your land.
The Treaty of Guadalupe Hidalgo sealed the American victory in 1848. For $15 million and the assumption that the Mexican debts to Americans, Mexico gave up its hold over New Mexico and California.
The territory included present day California, Nevada, Utah, and parts of Arizona, New Mexico, Oklahoma, Colorado and Wyoming. Mexico also agreed to finally relinquish all of Texas. Which includes the disputed area along the border. The U.S. Congress approved the treaty on March 10.