May 13 in American History

May 13, 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. 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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