History of the United States I / Unit 11 USH1 1542 worked example, 60 to 90 seconds
The Boundary Dispute
The idea
The United States had long argued that the Rio Grande was the border between Mexico and the United States. Mexico refused to be bound by Santa Anna's promises and insisted the border lay farther north, at the Nueces River. From Mexico's view, Polk's order sending troops into the disputed land was an invasion of sovereign territory. Setting the border at the Rio Grande would, in the anchor's words, allow the United States to control land it had never occupied.
In practice
A strip of country between two rivers, claimed by both governments and settled by neither.
Where people slip
Notice the asymmetry with Oregon. Polk campaigned on fifty-four forty or fight and settled at forty-nine without a fight, against a great power. He then went to war over a boundary in the south against a weaker one. That asymmetry is the strongest evidence that the war was about acquiring slave territory, and it is visible in the anchor's own numbers.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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