They will take over I believe
War and violence. While epidemic disease was by far the leading cause of the population decline of the American indigenous peoples after 1492, there were other contributing factors, all of them related to European contact and colonization. One of these factors was warfare.
The trans-continental railroad was completed around this time, so not only did train travel change, but was innovated so that a train could take you anywhere across the US.
The Greco-Persian Wars were two conflicts that occurred between 490 and 479 BCE and pitted the Persian Empire against the Greek city-states. The conflict began after Athens and Eretria gave assistance to the Ionians in their rebellion against Persia and its ruler, Darius. (got the answer from google hehe)