Gunnar Heinsohn: Augustus and Diocletian - contemporaries, or three centuries apart?
The purpose of the Roman empire’s subdivision by Diocletian and his tetrarchy was to permanently end the civil wars that had been raging since 88 BC (Marius [died 86 BC] against Sulla [died 78 BC]). This transformation from a more central to a more decentralized administration did not take place 300 years after these massive internal conflicts, but during the time that Augustus was still emperor. Diocletian did not organize decentralization to weaken Rome, but to protect the capital. Diocletian was not an imitator of Augustus's reforms. He was directly responsible for their implementation.
Augustus (Late 1st century BC) wearing the civic crown
Diocletian (3rd century AD) wearing the civic crown
The 1st millennium AD controversy
Hominids not to blame for loss of mega-fauna