Voivode (/ˈvɔɪˌvoʊd/) (Old Slavic, literally "war-leader" or "war-lord") is an Eastern European (Slavic as well as Romanian) title that originally denoted the principal commander of a military force. It derives from the word vojevoda, which in early Slavic meant the bellidux, i.e. the military commander of an area, but it usually had a greater meaning. In Byzantine times it referred to mainly military commanders of Slavic populations, especially in the Balkans. The title voievodos (Greek: βοέβοδος) was first used in the work of Constantine VII Porphyrogennetos "About administration of empire" to identify Hungarian military leaders.
In medieval Serbia it meant a high-ranking official and - before the Ottoman conquest in the 15th century - the commander of a military area. During Ottoman times, voivode was the title borne by the ruler of a province, whose powers included the administration, security and tax collection under a special regime. According to the chronicle of the Voutsas monastery, the Slavic title of “voivode”, which prevailed in certain areas of Epirus and Thessaly before the Ottoman conquest, used to denote the leader of a Vlach community or family. The same title was borne by the Ottoman official who oversaw the “Chora Metzovo” each time. The word gradually came to denote the governor of a province.