You receive a mysterious message from persons unknown, the message details a dangerous secret which is now up to you to keep safe. (work with your DM to determine details)
Rebellion: As an adolescent you joined a rebellion against the local ruler, if successful you are outlawed, if it failed you escape, with only friends and family knowing your involvement. (Work with your DM to detirmine the details)
You are plagued by incredibly detailed dreams, so detailed that you actually glean the future from the visions, either by interaction or observation. You begin to suspect, however, that the dreams are REAL, and that his two worlds will one day collide.