Debtors' prisons surface in England during the 1400s, although the practice of locking up those who can't or won't pay their creditors dates back to ancient Rome. During the Roman debtors' confinement, their debts were announced publicly on market days. After about two months, they were sold as slaves or killed. In 15th-century England and continental Europe, however, a debtor is imprisoned until the money is repaid. This isn't considered a criminal punishment. It is, rather, a way of resolving a private conflict between two citizens — a civil remedy. The debtors' prison offers some sort of recourse for lenders who have lost an investment.

Hanged Men
Hanged Men, Pisanello, c.1437