In 293 AD Diocletian and Maximian invited Constantius and Galerius to share in their Imperial burdens, forming what we today call the Tetrarchy.

Immediatly after becoming the undisputed Emperor in 285, Diocletian elevated Maximian to serve as his Imperial colleague.

The Crisis of the Third Century finally ended with the mini dynasty of Carus and his two sons. In 284 Diocletian rose to power, ushering in a new age in Roman history.

After Aurelian's death, an old Senator named Marcus Cluadius Tacitus briefly reigned before the throne fell to Probus, who ruled from 276-282.

Aurelian defeated the breakaway western provinces and reunified the Empire in 274 AD. The next year he was assassinated by officers who had been tricked into committing murder.

In 272 Aurelian finally managed to bring the east back under Roman control by defeating Queen Zenobia of Palmyra.

Aurelian became Emperor in 270 and immediatly faced an invasion of Italy by the Juthungi. After succesfully driving the Germans off, Aurelian turned his attention to building a new wall circuit around Rome to protect the capital in the future.

Claudius Gothicus became Emperor in 268 and promptly lead the legions to victories against the Goths and the Alamanni. Unfortunately he died before he was able to reunify the Empire.

The near simultaneous deaths of Gallienus, Odenathus and Postumus upset the political equilibrium in the late 260s AD.

The 260s AD were bad for the Romans, but they could have been a whole lot worse had not Gallienus, Postumus and Odenathus each done their part to defend their respective corners of the Empire.