Joint Resolution Annexing Texas | US House of Representatives: History, Art & Archives

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On March 1, 1845, President John Tyler signed a resolution annexing the Republic of Texas. From the article:

"After winning independence from Mexico in 1836, the Republic of Texas sought to become a part of the United States. The Texas minister to Washington proposed annexation to President Martin Van Buren in August 1837. The administration rejected the proposal, fearing reprisal from Mexico and the controversy that would follow the addition of another slave state.

In 1843, British interference in the annexation question—Britain opposed annexation in an effort to maintain trade with Texas and to thwart westward expansion by the United States—initially compelled President John Tyler to reconsider having the republic join the Union. His first attempt was rejected by the Senate in 1844, but annexation was ultimately realized by this joint resolution, signed by President Tyler on March 1, 1845. After the joint resolution was approved and a state constitution was drafted, Texas was officially annexed on December 29, 1845."