Congress declared war on Mexico after a border clash, beginning a conflict that would end with the U.S. gaining the vast territory of the modern Southwest. It was controversial even then — a young Congressman named Abraham Lincoln questioned its justification — and it deepened the slavery crisis by raising the question of the new lands' status.
Common Questions About May 13
What happened on May 13 in American history?
In 1846: the U.S. declares war on Mexico. Congress declared war on Mexico after a border clash, beginning a conflict that would end with the U.S.
Why is May 13 significant?
Congress declared war on Mexico after a border clash, beginning a conflict that would end with the U.S. gaining the vast territory of the modern Southwest. It was controversial even then — a young Congressman named Abraham Lincoln questioned its justification — and it deepened the slavery crisis by raising the question of the new lands' status.
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