We played a 3vs3 team game on LAN. One team tried to achieve a cultural victory. Our question is: is it possible to win if the 3 cities are owned by different players of the team? Or all 3 cities must be owned by one player?

I have no idea, but I'm posting because I'd like to know aswell.
I think they can, but someone will make sure.

I also have no clue, but can you gift cities to teammates and keep culture? I imagine you can because I doubt gifting a city to a teammate would take away the culture, consequently giving away the borders. Never tried that before except to give conquered cities occasionally.

I guess one way to check is to look at victories under f8 when playing a team game. If it has all three of your team's capitals at start, it probably is counting it as a team thing. But if it is only showing your capital, its just counting cities that you have.

I'm pretty sure this has happened to me/us once. I had two cities, my teammate had one achieving legendary status.

i imagine it is with 3x3. i know it is with 2 on a LAN, hubby and i have done it. i had one city, he had 2, but the three combined counted and we won.

you can even win a cultural victory single player in a one-city-challenge if you're in Permanent Alliance with an AI. you can't culture bomb their cities with great artists, but you can settle GAs there.

here (http://forums.civfanatics.com/showthread.php?t=167433) is how one SG did it.