Servant

You draw your pre-adventuring experience from a time of subservience. Perhaps you were a knight's page, the favorite slave of a warlord, a thrall in a vampire court, an indebted victim of a loan shark, an indentured worker in a factory, or a simple serf on a lord's property. But the work you did, even if you enjoyed it, was not entirely of your own volition, and now you have been released from service to your master, perhaps as a result of their death, buying your freedom with hard work and/or bits of wealth you scraped together, liberated by the band of a local hero, or even a daring escapade possibly involving others in your line of work.