The Republic of Texas formally declares independence from Mexico on March 2, 1836, at the convention of Washington-on-the-Brazos which was attended by 45 delegates, representing 21 municipalities. Over the next ten days, delegates prepared a constitution for the Republic of Texas; David G. Burnet was elected president.
The new constitution explicitly legalized slavery which Mexico had officially abolished in Texas in 1829. Texas was annexed by the United States in 1845 and became the 28th state on December 29, 1845. On March 2, 1861, Texas becomes the seventh state to secede from the Union. More