Mexican North or American Southwest: the Borderland in U.S.-Mexican Relations, 1821-1848

Abstract

In the year 1821, after a decade of convoluted struggle, an independent Mexico took the place of New Spain after nearly three hundred years of Spanish rule. Only two years previously the Spanish government secured the Adams-Orris Treaty with the United States, wherein, in exchange for relinquishing Florida and its claims to the Pacific Northwest, the disputed boundary between Louisiana and New Spain was set at the Sabine River, reserving Texas for Mexico. This was the border when independent U.S.-Mexican relations began, and from the beginning these relations were greatly influenced by their shared border. Indeed, this was the beginning of a process that, in thirty years' time, would result in the loss of fifty-five percent of Mexico's national territory to the United States.1 The US.- Mexican borderlands would be at the heart of this process.