Texes Social Studies Content Practice Exam

What established the boundary between Mexico and the United States after the Treaty of Guadalupe Hidalgo?

1. Sabine River

2. Red River

3. Nueces River

4. Rio Grande River

The correct answer is: Rio Grande River

The Treaty of Guadalupe Hidalgo, which was signed in 1848, ended the Mexican-American War and resulted in significant land cessions from Mexico to the United States. The agreement established the Rio Grande River as the official boundary between the two countries. This was a crucial decision, as it defined the territorial limits for the newly acquired lands, including what are now California, Arizona, New Mexico, Nevada, Utah, and parts of Colorado and Wyoming. The choice of the Rio Grande as the boundary was significant not only for geographic reasons but also for political and social dynamics of the time. It solidified U.S. claims to the territories in question and reflected the era's expansionist sentiment, often referred to as Manifest Destiny. Other rivers, such as the Nueces River, the Sabine River, and the Red River, were alternative boundaries proposed or used in earlier discussions, but they did not become the recognized international boundary established by this treaty. The choice of the Rio Grande has had lasting implications on U.S.-Mexico relations and ongoing discussions about border management and sovereignty.