in my game every single civ on earth ganged against Mansa. so after a couple of turn he became the vassal of Isabella. I dont know if it was capitulation but probably since peace was signed at the same time.

anyway, after a couple of turn, his land was above the 50% mark and since I was the only one who didnt attack him i was wondering if there was anyway to steal him to isabella. steal mansa from war or peace. anyone ever did that ? what are the ways to steal a vassal anyway?

the only thing i could come up is attack mansa and when he'd lose territory he would tell Isabella she cant protect him and sign with me...but that will hurt my diplo with mansa... I could attack Isa and do the same thing but there are no +++ in the diplo like " +2 you liberated us from our opressor" so are there any other way?

If he's captiulated no you can't steal him, he would have to meet either of two conditions:

A) His LAND AND HIS POP must become greater than 50% of Isabellas

or

B) He must lose more than 50% of his original lands since becoming a vassal

If he didn't capitualte, he can break free if either of the above conditions are met if he chooses to, the option to do so comes up about every ten turns.

So basically you have two options, go beat him up, or go beat her up (beat her enough her land and pop drops and Mansa gets the choice and he might take it, doesn't garantee he becomes your vassal however).

For more on Vassals go here:
http://forums.civfanatics.com/showthread.php?t=193747

You can declare war on Izi and force them into capitulation and then Mansa would no longer be a vassal to the spanish. Then force him to capitulate too or leave him he might come to you willingly once he is free and the Spanish can't help him.

i advanced in my war against izzy she capitulated. Mansa never wanted to join me...maybe also because he received a few nukes...

yeah they get a bit touchy when you nuke them for some reason