Aurelian, as we have seen, was on the point of invading Persia when a domestic conspiracy brought his reign and life to an end.

Tacitus, his successor, scarcely obtained such a firm hold upon the throne as to feel that he could with any prudence provoke a war.

But Probus, the next emperor, revived the project of a Persian expedition, and would probably have led the Roman armies into Mesopotamia, had not his career been cut short by the revolt of the legions in Illyria (A.D.

282).

Carus, who had been his praetorian prefect, and who became emperor at his death, adhered steadily to his policy.