Dario Calomino, Curator of Roman Provincial Coins at the British Museum writes:

Damnatio memoriae is the Latin phrase literally meaning "condemnation of memory" in the sense of a judgment that a person must not be remembered. It was a form of dishonor that could be passed by the Roman Senate upon traitors or others who brought discredit to the Roman State. The intent was to erase someone from history, a task somewhat easier in ancient times, when documentation was much sparser.

The sense of the expression damnatio memoriae and of the sanction is to cancel every trace of the person from the life of Rome, as if he had never existed, in order to preserve the honour of the city; in a city that stressed the social appearance, respectability and the pride of being a true Roman as a fundamental requirement of the citizen, it was perhaps the most severe punishment.

Lucius Aelius Sejanus suffered damnatio memoriae following a failed conspiracy to overthrow emperor Tiberius in 31. His statues were destroyed and his name obliterated from all public records. The above coin from Augusta Bilbilis, originally struck to mark the consulship of Sejanus, has the words L. Aelio Seiano obliterated.

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FEATURED WEB PAGE: DAMNATIO MEMORIAE (www.coinbooks.org/esylum_v16n14a27.html)