Who or What is Xrib?
Source: Altar of Xrib, UESP, Skyrim
Xrib was an obscure Aldmeri patron of Insects in the days before recorded history. They would enjoy a brief period of reverence by the Ayleids under the Flower King Nilichi before their extermination by the Alessians.
Xrib’s influence would later reach an all-time high after the disappearance of the Dwemer, when they taught their former Falmeri slaves how to herd and cultivate the giant chaurus native to Blackreach, saving them from starvation after the disappearance of the Dwemer, who they were dependent on for food.
A mythoreductionist would likely conflate the god with the Daedra Princes Mephala or Namira, or else the elven death-god Xarxes, given their role in contemporary Falmeri burial practice.
To the other Elven races, Xrib holds little influence or legacy, save for the derived term "scrib" referring to the ubiquitous giant insects of Morrowind