This is a community maintained page and does not represent official World of Warcraft history or occurrences. Information and events here are for community documentation of server particulars, history, or opinion.
Eitrigg opened up in early 2006 and opened to free transfers from multiple high population realms. <Musa> a guild originally from Bloodhoof (US-Alliance) came in as an already established high end raiding guild. Through progression of 40-man Ahn'Quiraj <Musa> collected all the server firsts until Twin Emperors. <Crusaders of Aegwynn> (Alliance) would go on to reach server firsts for Twin Emperors & C'Thun along with all of Naxxarammas. Although major success the guild would go on to lose almost all of its core players a few months prior to the release of The Burning Crusade. The realm is on CST and part of Battlegroup 6. PvE Progression moves steadily with the top guilds entering Sunwell on the cusp of Patch 3.0.2.
As of early 2009 the Horde side of Eitrigg has seen an exodus of guilds and players, increasing the population ratio which had already favoured Alliance over Horde by 2.5:1 or even 3:1. Census date on Alliance side is fairly inaccurate currently. This has resulted in Alliance having nearly a dozen full time 25-man raiding guilds while Horde has approximately half that. Various 10-man guilds flourish and press into Ulduar as well as PUG and form alliances with other guilds to enter the occasional 25-man.
Some of the following information may be out of date as guilds merge, disband, and are created on a daily basis. Perhaps the most current out-of-game resource for guild populations is the Warcraft Realms Census.