History of Thothia and Aran
by John CalvinOk, I'm steadily working my way back to the founding of Aran. This time I've pulled in a reference from the Savage Coast material that says the arenea there were concentrated around their city of Belphemon in BC 3400. If we assume that all aranea are descended from Arachne Prime's planar spider colonists, then this places the founding of Aran sometime before the BC 3400 and the GRoF.
There are also a series of events which we know need to happen in order to get the aranea from the Isle of Dawn to the Savage Coast, however most of these don't have any solid dates associated with them.
Timeline
BC XXX: Arachne Prime and her planar spider followers colonize the Isle of Dawn on Mystara and found the city of Aran.
BC XXX: Planar spiders intermingle with Mystaran "monstrous" spiders, creating the Aranea race.
BC XXX: Aranea (and their phanaton servants) leave the confines of Aran and the emigrate from the Isle of Dawn.
BC XXX: Aranea arrive in the Savage Coast and found the city of Belphemon.
BC 3400: Aranea are concentrated in Belphemon, their capital, beneath which lies a vast cavern system. Their civilization is thriving. [SC]
BC 2000: Aranea in Belphemon are replaced by the humans and demi-humans of Herath (actually aranea in disguise). [SC] [The aranea may have gained some new ability to conceal their true identity near this time.]
BC 994: Tokoramses V rules Thothia during the time of Alphatian colonization.
BC 426: Tokoramses XIV Builds the Temple of Dawn
AC 192: Ramenhotep X discovers Aketheti
AC 1000: Ramenhotep XXIII is the current ruler of Thothia