Any historical "invasion of technologically sophisticated aliens" in the time period blood meridian is set in happened centuries before. It's actually near a zenith of native political and military power. Spain is gone, Mexico is struggling to build a government, and the US hasn't yet become a dominant power in the region.

Blood meridian is a book I often recommend as an approachable introduction to what people experiencing the period might have thought, but framing the context is somewhat important.