The Mexican-American was fought between the Unites States and Mexico between 1846-1848. The underlying cause of the Mexican war was the movement of Americans into the lands of Mexico. In addition, the annexation of Texas in 1845 caused even more conflict between Mexico and Texas. The American citizen’s population had increased in Mexico territory, Northern State of Coahuila and Tejas. Mexico felt a threat, so the Mexican government started levying property taxes, prohibiting slavery, to reassert their authority over Texas. The biggest potential problem was that Texas wanted Mexico to agree, that the Rio Grande River as the South Western boundary of Texas. For the Americans controlling the Wester lands up to Rio Grande, were closer owning
