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Annexation of Texas

29 Dec 1845 — Texas enters the Union as a slave state through a joint resolution of Congress. The resolution needs only simple majorities; an annexation treaty had failed in the Senate in 1844. Mexico had already broken off relations and warned that annexation meant war.

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Map: Annexation of Texas, 29 December 1845
29 DECEMBER 1845 · THE AMERICAN CIVIL WAR, 1840–1877

The moment in context

In the 1840s, Americans traveled west in growing numbers, and expansionists expected the government to secure the lands they entered. They called their cause Manifest Destiny: Providence, or God’s plan, had supposedly assigned the continent to the United States. This promise of national greatness carried a racial assumption that white Americans should rule. President James K. Polk made expansion a policy. Texas, a slaveholding republic since its break from Mexico in 1836, entered the Union in 1845 by a joint resolution of both houses, after the Senate rejected an annexation treaty. Britain and the United States divided Oregon at the 49th parallel, now the Canadian border; its hatching disappears from the map in June 1846.

From Mexican–American War, chapter 1 of The American Civil War, 1840–1877 (JUL 1848).

The place: Annexation of Texas — map and full story →

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The American Civil War, 1840–1877
13 CHAPTERS · AN INTERACTIVE SITUATION MAP

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