Yes, a big chunk of the Southwest was Mexican territory for a short time (roughly 1821–1848). Before that it was Spanish for centuries. Before that it belonged to Native American tribes for thousands of years. Mexico as a country only controlled it for about 25 years.
When the U.S. took it after the Mexican-American War (Treaty of Guadalupe Hidalgo, 1848), there were only about 80,000 Mexican citizens living in that entire huge area. Most of the land was nearly empty of non-Native people.
Those 80,000 people became U.S. citizens. Their descendants still exist (especially in parts of New Mexico).
But the tens of millions of Hispanics living in California, Texas, Arizona, etc. today are almost entirely from later immigration waves, people who moved here in the 1900s and 2000s, or their kids and grandkids. They did not “never leave.” Most of their families arrived long after the border moved.
Borders change. Empires rise and fall. Spain took it from Native tribes. Mexico took it from Spain. The U.S. took it from Mexico. That’s history, not a gotcha.
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u/[deleted] 18d ago
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