I want to know the answer to the following question:
Why is  there still Bilingual  spoken in these states?
All the background I'm provided with is that "After the Mexican War of Independence from Spain also, California, Nevada, Arizona, Utah, western Colorado and southwestern Wyoming became part of the Mexican territory of Alta California and most of New Mexico, western Texas, southern Colorado, southwestern Kansas, and Oklahoma panhandle were part of the territory of Santa Fe de Nuevo México.". Is that enough to answer the question?