These are timelines that have as their POD(s) alternate developments in various indigenous cultures of the Americas (North America, Central America and the Caribbean, South America).
There have been a fair few Native American timelines, major and minor, throughout AH.com's history and the history of the online AH community in general. Here's a (mostly) alphabetically sorted list of some notable timelines. A list of various Native American focused timelines and AH stories on AH.com, written by various authors over the course of two decades. Well worth reading.