[Nubben]

My guild Silens Dauthus on Mithaniel Marr did a /guildwar at one point. If I remember right, the /guildwar command also had parameters that would set the duration in days, at which time it would automatically end.

Silens Dauthus was an all rogue guild, and the guild we "warred" with was a druid/ranger guild. I think only one or two people from each guild actually managed to pvp during the guildwar, as our guild was mostly centralized in the Butcherblock area at the time, and they were all in/near Misty Thicket so it was pretty much pointless. I know that I never saw a member of the other guild during the "war." This was either pre-Kunark or shortly after the release, definitely pre-Velious though.

Some friends of mine participated in a player ran event on another server (I think Tarew Marr) that was based on a guild war. Two guilds were created specifically for the event, with names like "Army of the East" and "Army of the West" or something similar. Players were allowed to level up to 10, and the people running the event gave players spell money and some leather/banded armor and stuff. Everyone from both guilds then went to Tox forest and the guilds went to "war."

I wasn't there for the event, but it sounded like a cool idea and my one friend made out with some pretty cool items from participating, enough so that he switched to that server permanently and eventually was able to trade his way up to some top end items like AoN and Fungi despite never making it past level 35 or so.