[Sidenote: Texas admitted by joint resolution, 1845. _McMaster_, 325.]
332. Acquisition of Texas, 1845.--Tyler now pressed the admission of Texas upon Congress. The two houses passed a joint resolution. This resolution provided for the admission of Texas, and for the formation from the territory included in Texas of four states, in addition to the state of Texas, and with the consent of that state. Before Texas was actually admitted Tyler had ceased to be President. But Polk carried out his policy, and on July 4, 1845, Texas became one of the United States.
[Sidenote: War declared, 1846. Lowell in _Source-Book_, 271-276.]
333. Beginning of the Mexican War, 1846.--The Mexicans had never acknowledged the independence of Texas. They now protested against its admission to the United States. Disputes also arose as to the southern boundary of Texas. As no agreement could be reached on this point, President Polk ordered General Zachary Taylor to march to the Rio Grande and occupy the disputed territory. Taylor did as he was ordered, and the Mexicans attacked him. Polk reported these facts to Congress, and Congress authorized the President to push on the fighting on the ground that "war exists, and exists by the act of Mexico herself."
[Sidenote: The three parts of the Mexican War.]
[Sidenote: Taylor's campaign. _McMaster_, 326-327.]
334. Taylor's Campaigns.--The Mexican War easily divides itself into three parts: (1) Taylor's forward movement across the Rio Grande; (2) Scott's campaign, which ended in the capture of the City of Mexico; and (3) the seizure of California. Taylor's object was to maintain the line of the Rio Grande, then to advance into Mexico and injure the Mexicans as much as possible. The battles of Palo Alto and Resaca de la Palma (May 8, 9, 1846) were fought before the actual declaration of war. These victories made Taylor master of the Rio Grande. In September he crossed the Rio Grande. So far all had gone well. But in the winter many of Taylor's soldiers were withdrawn to take part in Scott's campaign. This seemed to be the Mexicans' time. They attacked Taylor with four times as many men as he had in his army. This battle was fought at Buena Vista, February, 1847. Taylor beat back the Mexicans with terrible slaughter. This was the last battle of Taylor's campaign.