This is a tetradrachm from Alexandria in Egypt. It depicts Emperor Marcus Aurelius Probus on the obverse and an Eagle on the reverse.
Probus was born in AD 232 in Sirmium (modern day Sremska Mitrovica in Serbia) and became emperor in AD 276. In AD 278, he successfully campaigned against Gallic tribes that pushed into Roman territory, and in AD 279 – 280, his generals defeated Vandals in the Roman provinces of Raetia, Illyricum, and Lycia. In the same years, Probus’ generals defeated the Blemmyes in Egypt.
In AD 280–281, Probus put down three usurpers, Julius Saturninus, Proculus and Bonosus. In AD 281, the emperor was in Rome, where he celebrated his triumph.
He left Rome in the spring of AD 282, and travelled to Sirmium, where he was preparing to wage war against the Persians.
In September AD 282, the commander of the Praetorian Guard, Marcus Aurelius Carus, was proclaimed emperor by his troops.
Probus sent troops against the new usurper, but when his troops changed sides and supported Carus, Probus’s remaining soldiers assassinated him at Sirmium in late September AD 282.
The coin is one of the last of the tetradrachms minted in Alexandria for exclusive circulation in Egypt. The L and Z on either side of the eagle indicate it was minted in the 7th year of Probus’s reign, AD 281 – 282. Diocletian, who succeeded Probus, transformed the Alexandrian mint into one which issued the more common coins (folles) for general circulation in the east.
Thank you to Paul Anderson of Praefectus Coins for his assistance in identifying this coin and providing the provenance of the coin.
Thank you to the Illustrated History of the Roman Empire (website: http://www.roman-empire.net/decline/probus.html) and to the Wikipedia article (website: https://en.wikipedia.org/wiki/Marcus_Aurelius_Probus) for the information on Emperor Probus