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Which territories were administered by Diocletian in the tetrarchy?
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Diocletian
Diocletian.
Under the tetrarchy established by Diocletian, the Roman Empire was divided into four administrative sectors, each overseen by one of the four rulers. While the empire remained an undivided inheritance, these sectors allowed for more efficient governance and military defense.12
Diocletian, who resided in Nicomedia, was responsible for the administration of the following territories:
The other three rulers managed the remaining regions of the empire:
* Galerius (residing in Sirmium): Illyria, the Danubian provinces, and Achaea.12
* Maximian (residing in Milan): Italy, Sicily, and Africa.12
* Constantius I Chlorus (residing in Trier): Gaul, Spain, and Britain.12