This map, created by Konstantinos Plakidas for Wikimedia Commons in 2009, shows the extent of the Byzantine Empire in 1025, upon the death of Emperor Basil II.
Basil II was one of the most important emperors of the Byzantine Empire. He was in power for almost half a century, between 976 and 1025, during which time he managed to expand the empire to its greatest extent in four centuries. Among other things, he defeated the First Bulgarian Empire and the Fatimid Caliphate, as well as conquering part of Crimea.
The map also shows the territorial administration of the Byzantine Empire. Its main administrative divisions were the themes, which were established in the second half of the 7th century and remained in place until the 12th century. Some of the themes enjoyed a degree of autonomy, as was the case with Serbia and Croatia. Others were part of one of the four regional duchies that existed in the east of the empire: Mesopotamia (blue), Baspracania (yellow), Caldia (orange) and Antioch (green).
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