Try wikipedia for Precession (of the Equinoxes) or the Yugas (in Hindu cosmology) - The Mayans, Aztecs and Hopi have similar cosmologies that described 26K year old cycles.

I wrote a piece called Forging Peace has a variety of resources about the coming new worldview from an inner perspective with outward manifestations.

https://medium.com/know-thyself-heal-thyself/forging-peace-772129ee3c33