In the first decades of the sixteenth century, Moldavia became vassal of the Ottoman Empire. From 1511-1512, Bogdan III officially fulfils new bonds to Ottoman power as a vassal of the Turkish sultan. The ruler of Moldova only accepted formal suzerainty of the sultan, the country kept till 1538 powers to promote its own external policy. It was followed by the stage 1538/1541 – 1711 when Ottoman hegemony could effectively and for long establish in Moldova. The transition from one stage to another was done quite slowly, being a continuous process. The effective and long term regime of Ottoman suzerainty has resulted in the establishment of a comprehensive system of economic and financial, political and military obligations of the Romanian States to the Porte