God-Emperor
Deity
If a civ capitulates to someone they are at war with then the war is over. Everyone who was at war with them is now at peace with them. Nobody automatically declares war on the new master from this (it may alter the diplomatic situation enough that they will soon do so, but it is not automatic). Anyone who was at war with the new master before the capitulation will still be at war with them.
If a civ who is in a war becomes the vassal of someone who was not at war with them, then the war continues and everyone who was at war with the that civ is now at war with their new master too. It is the cost of accepting a civ that is at war as a voluntary vassal: the new master inherits the wars of the vassal.
If a civ who is in a war becomes the vassal of someone who was not at war with them, then the war continues and everyone who was at war with the that civ is now at war with their new master too. It is the cost of accepting a civ that is at war as a voluntary vassal: the new master inherits the wars of the vassal.