In a dark alley at night, you are attacked by thugs. Before they can take anything, they turn white with terror and run away. You discover that you have a guardian ghost, a wise, benign spirit who accompanies you (work with your DM to determine details)
Poverty You or your family fell on hard times and were unable to pay taxes, resulting in either your character or a family member spending time in prison. Work with your DM to detirmine the details)
In adulthood you have an encounter with an unusual person, who as far as you can tell, has no home or family. You offer to help in anyway you can. After accepting your hospitality the stranger vanishes leaving a note "Your kindness will be remembered".
Political. A politcial enemy might inlcude a local magistrate, a noble who rules the region, or a monarch ruling the kingdom. the NPC might have offended a local ruler,become an outlaw, or a be a political rival.