Texas was the ___ state to be annexed to the United States.

Texas was the 28th state to be annexed to the United States. Texas declared independence from Mexico in 1836 and, following nearly a decade as an independent republic, it joined the U.S. on December 29, 1845. Understanding the sequence of states' admission is crucial to grasping the historical context of U.S. expansion and the significance of Texas in that narrative. It emphasizes the political and social dynamics of the time, including issues related to statehood, slavery, and the balance of power in the newly formed union.