What year did the US adjust the Texas/ New Mexico Borders?

Question

Hi! I need to know what year the Texas and New Mexico borders were changed by the United States government. I have looked everywhere I know and haven't been able to find the date.

Thanks in advance!!

Answer 1

i believe that it started in 1869 -1870's

Answer 2

The Rio Grande river has, since 1848, marked the boundary between Mexico and the United States from the twin cities of El Paso, Texas, and Ciudad Juárez, Chihuahua, to the Gulf of Mexico. As such, it was across this river that Texan slaves fled when seeking their freedom, aided by Mexico's liberal colonization policies and abolitionist stance.