IIRC, Texas was forced to join the Union.
***Texas was forced to join the Union.***
Actually it was Great Britain that caused it. Britain recognized Texas with the Rio Grande as the southern border. They hoped to forge an alliance with Mexico, Canada, and Texas against the US over the Oregon territories.
Texas was so shocked at such an alliance against the US they applied for admission as a state, and got it. The US sent troops to the north side of the Rio Grand, which Mexico claimed as their own. Mexican forces began a bombardment of the outpost which was named Ft Brown, after the first soldier killed there, and the war was on!
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.... After some sparring, Houston consented to the negotiation of a treaty of annexation, which was rejected by the United States Senate in June 1844. Annexation then became an issue in the presidential election of 1844; James K. Polk, who favored annexation, was elected. Tyler, feeling the need of haste if British designs were to be circumvented, suggested that annexation be accomplished by a joint resolution offering Texas statehood on certain conditions, the acceptance of which by Texas would complete the merger. The United States Congress passed the annexation resolution on February 28, 1845, and Andrew Jackson Donelson proceeded to Texas to urge acceptance of the offer.
Public opinion in Texas, fanned by special agents from the United States, demanded acceptance of the American offer. President Anson Jones called the Texas Congress to meet on June 16, 1845, and a convention of elected delegates was assembled on July 4. He placed before both bodies the choice of annexation or independence recognized by Mexico. Both Congress and the convention voted for annexation. A state constitution, drawn up by the convention, was ratified by popular vote in October 1845 and accepted by the United States Congress on December 29, 1845, the date of Texas’s legal entry into the Union. The formal transfer of authority from the republic to the state was not made until a ceremony held on February 19, 1846. President Anson Jones handed over the reins of state government to Governor James Pinckney Henderson having declared “The final act in this great drama is now performed; the Republic of Texas is no more.”
State of Texas Historical Society
https://www.tshaonline.org/handbook/online/articles/mga02
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