enticing AI to war

[TKG]

well you could pick civilizations that traditionally dont like each other.

 

[Argetnyx]

ally with their enemies, set trade embargoes against them, demand tribute, don't allow them to enter your territory, those usually work well.

But the best way is to use the 'Sub Bug', build a lot of subs and send them out to their coastal cities.

 

[iambenben]

if you have the intelligence agency later in the game you could always end production in their cities or even try and plant spies, if they are caught multiple times then they declare, in my current game i managed to get a coupla wars from just trying to plant spies (intentionally to start a war)

 

[thetrooper]

Leaving a coastal city with one (or more Privateers) may cause a naval vessel to bombard the Privateer (considered barb). This will cause that civ to DOW you. Note1: this happened in one of my games. I have not tried to 'reproduce' the event in others. Note2: the city must be coastal and only be 'guarded' by Privateer(s). I take it as a too cheap trick to play on with, but then again 'leave or declare' multiple times (as others have said) is IMHO equally cheap...

 

[Argetnyx]

The very best way is alliances, like WWI