How did Mexico's territory change over time?

At the beginning of the 16th century, the territory of modern-day Mexico was home to powerful civilizations such as the Maya and the Aztecs. This changed after the arrival of the Spanish, who conquered the region and incorporated it into their empire. Mexico became part of New Spain, and many Spaniards settled there. Over time, a deep social divide formed, as Spaniards born in Mexico were granted fewer rights than those born in Spain, leading to growing resentment.

The situation worsened when Napoleon took control of Spain, weakening Spanish authority overseas. After years of unrest and rebellion, Mexico achieved independence in 1821. The newly independent country controlled a vast territory, stretching far beyond its present-day borders and covering much of North America.

As the United States expanded westward, American settlers moved into Texas, which was then part of Mexico. Tensions grew, and Texas eventually declared independence before joining the United States in 1845. Mexico viewed this as an act of aggression, which led to war between the two countries. Mexico, weakened by political instability and limited resources, struggled to defend its territory. U.S. forces advance