In the new Civilization 5 Brave New World expansion I had the unhappiness level jump from 2 to 32 in one turn, and then to 44 the next turn for no discernible reason. Roughly a third of my cities were puppets. I replayed this scenario a half dozen ways and no matter what I did the unhappiness level jumped the same amount within the same short period of time. Any ideas?
It sounds very much like someone with a lot of tourism influence over you just became part of an ideology different to your own. Or the world ideology was voted on, and it's different to yours.
If you can provide more information about the situation, I can give you more suggestions as to the cause.