Since the Thirteen Colonies, suffrage was restricted often to a few qualifications, for example, Plymouth Colony restricted suffrage to only freemen orthodox in the fundamentals of religion. Later, in colonial New York, suffrage did not require religious test but it was restricted to men landholders. In Virginia, white freeman was allowed to vote. Later, slowly all the colonies demanded white males own property to have the right to vote. Only around 1856 that property ownership was left out of the demands to vote, but suffrage was still restricted to white males.
Conflict with Mexico began when the United States annexed Texas as a state in 1845. Mexico claimed that the new border between Texas and Mexico was the Nueces River, while the United States contested the border was the Rio Grande.
