The question of who could be legally enslaved in the early modern Mediterranean was one not simply of religious identity—of Muslims enslaving Christians and Christians enslaving Muslims—but also, in the Ottoman case, of juridical subjecthood. The enslavement of Ottoman non-Muslim subjects was strictly forbidden under Islamic and Ottoman law, as was the enslavement of the subjects of the Ottomans’ treaty-partners, such as Venice during the long period of peace between 1573 and 1645. Nevertheless, in this period local administrators and pirates in the Ottoman Balkans formed human trafficking networks with their counterparts across the Mediterranean in the de facto independent port cities of North Africa in order to circumvent these prohibitions. Along the Adriatic, Ionian, and Morean coastlines and further inland, Ottoman naval irregulars, amphibious strongmen, and district governors frequently conducted raids on Ottoman Christian villages and captured Ottoman subjects, Venetians, and others whom they were bound by law and treaty not to molest. To disguise the provenance of their captives and realize maximum profits with minimal interference, such raiders engaged in what I call “slave laundering,” shipping those illegally enslaved to North Africa where the Ottoman center would have little chance of finding or redeeming them and where the captives themselves would be unable to summon the witnesses necessary to prove their subjecthood and free origin in the courts. In Ottoman North Africa, such captives could be exchanged for slaves of acceptable, “enemy infidel” origin for export back to the Balkans or simply sold for cash. Based on research in Ottoman administrative and court documents, this paper explores the trade in illegally enslaved persons in the Ottoman Mediterranean, the difficulties inherent in defining and determining subjecthood on the ground, and the administrative and legal tools the Ottoman central government employed, often though not always in vain, to locate and identify the illegally enslaved and effect their return home.