Texas was admitted to the United States a slave state. The annexation of Texas contributed to the coming of the Mexican American War (1846-1848). The conflict started, in part, over a disagreement about which river was Mexico's true northern border: the Nueces or the Rio Grande
Southerners] have all kinds of ways of drawing lines and resisting the egalitarian impulses of freedom, the assumptions of the former slaves, just setting up roadblocks
