Stemming from its primeval origins in ancient notions of punitive punishment, by medieval times, Chinese slavery had already long ago become culturally embedded enough to function effectively as an invisible institution, practiced endogenously as well as exogenously. Since earliest times, slave status in medieval China, which was a class-bound, inheritable, and thus only rarely escapable condition, tended to befall either the surviving dependents of executed elites who had contravened authority or else those oftentimes non-Chinese unfortunates—combatants or otherwise—who were captured alive in battle or simply taken by force. Additionally, at any time, exigency could compel the sale of children into slavery. Slaves themselves were divided into two broad categories according to ownership, being either official slaves or private slaves. A crucial development of the medieval age is that both types of slaves came to be accounted for in the dynastic legal codes, which was an especially important occurrence for private slaves because, for the first time, their treatment by their masters became regulated. Finally worth noting in the medieval Chinese case is the prominence of specialized functionaries who, although unfree by any measure, were not typically regarded societally as slaves. Included under this rubric were eunuchs and concubines.