
Originally Posted by
TheLoadbearer
Well, Stormwind was dissolved before the Grand Alliance was formed, but before it was broken by Arthas and the Scourge, I have no doubt that Stormwind joined it. The US was one of the primary founders and remains the primary funder of the United Nations, but it would still remain in some capacity if the US left it or was destroyed by some enemy.
The state of the AoL in WC2 was:
All human kingdoms minus Alterac when the rest of the Alliance attacked them as punishment for their king's betrayal, Quel'thalas, Khaz Modan, and the gnomes.
By the time of Vanilla WoW, Gilneas had pulled their support and walled themselves off, showing no semblance of friendship.
Stromgarde had pulled back when Terenas refused to execute the orcs, but they always remained friendly to the other kingdoms.
Quel'thalas left at the end of WC2 citing elven casualties, but really they just didn't want to be involved in what they saw as human affairs anymore. They were still friendly to the Alliance in the same way as Stromgarde however, and Kael'thas gladly rejoined them to help fight the Scourge, and it was still the supposed Grand Alliance of Lordaeron, as he calls it a "failing Alliance" when it seems to be crumbling under Garithos' leadership. By Vanilla WoW, the Blood Elves were dealing with their own problems in Azeroth, but the High Elves remained friendly to the Alliance.
Dalaran was weakened and gathering their strength, but still technically members. It wasn't until WotLK that they declared themselves neutral officially (not just small groups of NPCs outside Karazhan) and could be considered to no longer be Alliance members.
Kul Tiras left when Daelin died and the rest of the Alliance refused to help avenge him, so they were gone by Vanilla.
(Bolded groups are those who remain as active members, not merely friendlies, from WC2 days at the time of Vanilla and no later)
Grand Alliance of Lordaeron Members
Lordaeron
Gilneas
Stromgarde
Kul Tiras
Dalaran
Stormwind (remnants)
Bronzebeard Dwarves
Wildhammer Dwarves
Gnomes
Quel'thalas
Vanilla Alliance Members
Lordaeron (remnants, such as Hillsbrad humans, and the Scarlet Crusade who considered them allies and were sent aid in the form of players who discovered their fanaticism.)
Dalaran (however weakened they were)
Stormwind
Bronzebeard Dwarves
Gnomes
Night Elves
So most of the Vanilla groups were original members, even if Stormwind wasn't technically active as a kingdom at the time, its soldiers certainly were, and their pooled army was led by Anduin Lothar from Stormwind. I include Lordaeron groups like those in Hillsbrad and not others like elves at Quel'lithien Lodge or the dwarves at Aerie Peak because they seemed more just friendly, and not active members who considered themselves Alliance and enemies of the Horde.