Arathor was the first great human nation — and eventual empire called the Empire of Arathor or Arathorian Empire — founded by a unification of the various tribes of the Eastern Kingdoms under the Arathi. Its capital was Strom, now known as the semi-abandoned fortress of Stromgarde.
Creation and war
Concerned that the trolls were becoming too great a threat, the Arathi tribe of humans embarked on a campaign to conquer its rivals through combat and politics. By offering equality and peace to the people they conquered, the Arathi were able to form a powerful nation, Arathor. The capital of Strom was built, and the humans in the area. that would later become Lordaeron, travelled to its protection.
The high elves of Quel'Thalas, meanwhile, were in open war with the trolls. On the verge of defeat, they sent ambassadors to Strom to plead for assistance from the human king, Thoradin. In exchange for support, the elves agreed to instruct one hundred humans in the use of magic. Through the military might of Stromgarde, and the magic wielded by the elves and new human mages, the trolls were soundly defeated. This great conflict, and first large scale war in the Eastern Kingdoms, was later dubbed the "Troll Wars".
Following the defeat of the trolls, the human mages that had been instructed by the high elves eventually chose to leave Strom and found their own nation, Dalaran, dedicated to the study and use of magic. In time, other city-states were founded: Gilneas, Alterac, and Kul Tiras. Much of the nobility decided to move from Stromgarde to the fertile lands of the north, founding Lordaeron, while the heirs of King Thoradin travelled far south to form the kingdom of Azeroth (later known as Stormwind). The few remaining loyal defenders of Strom renamed it Stromgarde, a shell of what was left of a once-great empire.
The human nations that splintered off from Arathor would not be united again until the Second War, in which the Alliance of Lordaeron was formed to defeat the Orcish Horde. Lord Anduin Lothar, as the last descendant of the Arathi, was able to call upon the high elves to join this new alliance of many races in payment of the help provided by the humans of Arathor during the Troll Wars.