Ever since getting BtS I haven't had the need or desire to form more than one colony, but much to my surprise I found out something startling when I did in my current game. Even though on the screen it stated "Cannot declare war!!!" regarding my vassal, Washington, when I formed my second colony it abruptly declared war on my own +40 relations vassal.

This seems rather puzzling to me, why would this happen? From a realism perspective, an empire can obviously have more than one vassal (I already had two, and have never encountered a limit in the past years...), and from a gameplay perspective I'm pretty sure I can just wait 10 turns and re-vassalize my old friend again, since he has more than +20 relations even after the war declaration. It was very surprising and unpleasantly unexpected, as I don't remember seeing in any of the documentation I read indicate there is a limit on the number of colonies you can have.

I'm not even sure if it was a population or land split, as there are no population/land statistics displayed for Washington when I hover over his name, as there are for Gilgamesh, my capitulated vassal.

You annihilated someone that was at war with Washington when you killed him. Your new colony inherited the annihilated civ's place, and declared war on washington. You got dragged into it.

It's a bug that Bhruic's unofficial patch fixes.

A known problem. Have you installed 'Bhruic's Unofficial Patch' ?

Thanks! Thought I had that installed already...

Three years, 999 posts... slow but steady. Hmm... to make an extra post or not to make...

It's easy to accidentally put it in the wrong place, especially if you have the Steam version of BTS. Be very careful that you are copying the DLL to the correct folder.

An easy way to verify that you have it installed correctly is to check whether your cities' build menus have +culture in the tooltips.

That's a rather huge bug; why hasn't Firaxis fixed this yet?

It seems that someone is asking this question every other day on this forum. I know it was the first post I made. This should be stickied so that all can see it.