Conference of Carnuntum
308 CE.
Shown on the map at 48.116°, 16.859°.
The Conference of Carnuntum was a gathering of ancient Roman rulers on 11 November 308, intended to stabilize the power-sharing arrangement known as the Tetrarchy. It was convened by the Eastern augustus (emperor) Galerius (r. 305–311) in the city of Carnuntum (present-day Petronell-Carnuntum, Austria), which at the time was located in the Roman province of Pannonia Prima. A dispute over the title of augustus in the West had been ongoing since the previous year, when consecutive invasions by Severus II (r. 306–307) and Galerius had failed to recover Italy from the usurper Maxentius (r. 306–312) and Maximian (r. 286–305, 306–308). Present at the conference were the retired Diocletian (r. 284–305), and his former colleague, Maximian. According to deliberations at the meeting, Maximian was to retire permanently from his imperial position, and Maxentius was still to be treated as a usurper; Licinius (r. 308–324), a former general of Galerius, was raised as the western Augustus and made responsible for overthrowing Maxentius; and Constantine (r. 306–337) was relegated, for the second time, to western caesar.
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