Why are FPS teams called "clans"?

In some genres, but especially in FPSs, teams of players are often called clans. Why was this specific word chosen?

This is in contrast to guild or faction in RPGs, but here I can see why - they are analogous to actual guilds or factions within the lore or setting.

Clan however doesn't make much sense to me. The word itself implies kinship, and doesn't really fit with the typical FPS themes during the rise of online gaming - mid-to-late 90's - which were mainly sci-fi or militaristic.

Was there an influential game or community that first used clan (and why), and it simply spread? Or is there some other reason why this word was chosen?

Solution 1:

As far as I am aware, the use of the term "clan" to refer to a group of players of a game was popularized by Quake.

Quake's multiplayer capabilities were pivotal to the nascent e-sports scene along the broadening availability of broadband internet, so it was one of (if not the) first FPS around which competitive and co-operative groups would form, communicate and self-identify on a scale that only the internet could foster.

The name likely came from Quake's gothic, medieval feel, although I can find no concrete information on who first coined the term. It has persisted as a common group moniker for FPS games since Quake itself was an FPS.

The concept of a calling a group of players something like a "clan" or "guild," however, is definitely older than Quake (references to guilds with "guild tags" can be found in Computer Gaming World back issues from the 1980s, specifically issue #29, in an article about Island of Kesmai, a CompuServe MUD).

Solution 2:

The terminology "clan" is derived from the two different factions of the PC game "MechWarrior 2" released in 1995. (Quake was release 1996) The player could choose to be a member of one of two clans, either Clan Jade Falcon or Clan Wolf. Later more Clans from "Battletech Universe" could be selected.