What does "This faction is currently unavailable" mean?

The full message reads "This faction is currently unavailable on this ruleset due to population imbalance": the side you picked is closed right now on this ruleset because of a population gap. It isn't a bug; it's Blizzard's faction balance system.

This faction is currently unavailable summary card: faction balance lock, appears on PvP rulesets, fix is to wait, pick the other faction or another ruleset
What the message means
Source / rights
Image / usage information: Summary card drawn by wowguide.net; background (c) Blizzard Entertainment, Inc. from the official WoW: Forever launch news post. · Image source ↗

Blizzard announced it ahead of launch in its ruleset article: PvP rulesets get systems that keep Horde and Alliance populations closer together. As in Season of Discovery, new character creation can be temporarily limited for a faction when needed.

Short answer

This message appears when one faction outnumbers the other on a PvP ruleset: Blizzard pauses new characters for that side. Try again later, pick the other faction, or move to Normal or RP, where both factions are open.

Which rulesets does it show up on?

The system is for the PvP rulesets. On Normal, Roleplaying and Hardcore you can make characters on both factions. PvP adds one more rule: once you make an Alliance character there, you can't make a Horde one on the same ruleset, and the other way round.

On launch night the official forum thread for this message passed 300 replies on day one, with most players saying Horde was the locked side on PvP. Blizzard hasn't said what gap triggers the lock or when it lifts.

What to do if you can't make your character

  1. Try again later. The limit is temporary, and the faction can reopen as populations even out.
  2. If you want to start now, pick the other faction on PvP.
  3. If the faction matters more, move to Normal or RP, where both sides are open.
  4. Playing with friends? Agree on the ruleset and faction together first.
A road climbing to a walled city on a hill
Image: Blizzard Entertainment
Source / rights
Image / usage information: © Blizzard Entertainment. Resmi World of Warcraft: Forever görüntüsü. · Image source ↗

Every ruleset is greyed out

On launch night some players got through the queue and found every ruleset unavailable. That's different from the faction lock and comes from server load. Start with the steps on our server status and login queue page.

FAQ

Can I have characters on both factions on PvP?
No. Per Blizzard, the PvP ruleset allows one faction. For both sides, use Normal, RP or Hardcore.

Related guides

WoW Forever realms and rulesets explained · WoW Forever errors and fixes