USA HISTORY

Detailed explanation-1: -Texas claimed the Rio Grande as its southern border. Mexico said the Nueces River, to the north, should be the border. The dispute simmered until Dec. 29, 1845, when the U.S. annexed the Lone Star State, and sent troops to the Rio Grande a month later.

Detailed explanation-2: -Mexico also relinquished all claims to Texas, and recognized the Rio Grande as the southern boundary with the United States.

Detailed explanation-3: -The current border was originally decided after the Mexican–American War (1846–1848). Most of the border is settled on the Rio Grande River on the border of Texas and northeastern Mexico.

Detailed explanation-4: -After the Mexican-American War-during Texas’ first round of being a U.S. state-the 1848 Treaty of Guadalupe-Hidalgo established the Rio Grande as the border between the United States and Mexico.

Detailed explanation-5: -The Rio Grande serves as the border here. “The Rio Grande is a natural border, has been since 1848, and the ties between cities and towns on either side are strong, ” CNN’s Gregory Krieg reported.