USA HISTORY

Detailed explanation-1: -On June 23, 1845, a joint resolution of the Congress of Texas voted in favor of annexation by the United States. The leaders of the republic first voted for annexation in 1836, soon after gaining independence from Mexico, but the U.S. Congress was unwilling to admit another state that permitted slavery.

Detailed explanation-2: -In 1844, Congress finally agreed to annex Texas. On December 29, 1845, Texas entered the United States as a slave state, broadening the irrepressible differences in the United States over the issue of slavery and setting off the Mexican-American War.

Detailed explanation-3: -In 1845, the Republic of Texas was annexed to the United States of America, becoming the 28th U.S. state. Border disputes between the new state and Mexico, which had never recognized Texas independence and still considered the area a renegade Mexican state, led to the Mexican–American War (1846–1848).