Although the fact that the international slave trade was highly improved during the Abbasid period is mentioned by the historians frequently, the studies that thoroughly inquire its causes have not been conducted so far. The main difficulty here is that the international slave trade is a complicated subject that cannot be solely explained by the internal dynamics of the Abbasid Caliphate or the Abbasid Era. Since the prisoners of war that were captured during the conquests and battles by the Muslims were employed as slaves until the rise of the Abbasids, the Muslims did not have to establish a connection with the international slave trade. However, the Abbasid Era was not the epoch of the grand conquests; rather, it was generally affiliated with the political schisms and mass territorial losses. The narrowing of the tobe-conquered and to-be-raided lands had slowed down the influx of the slaves through the Islamic World by these methods. Thus, the Abbasids were able to eliminate their human force problem by consulting to the international slave trade with the help of their immense economy and mercantile links. The warrior peoples and the professional traders were partners in this trade. The partnership and trade among these three partners lasted along A.D. IXth and Xth. centuries. Eventually, the slaves that were once the promised booties of the veterans and the conquering warriors; became the commercial luxury commodities in the Abbasid Era.