Damnatio memoriae

ancient Roman punishment on traitors or those who brought discredit to the Roman State, consisting of removal of their names from inscriptions and documents, destruction of their depictions, and sometimes even large-scale rewritings of history

The face at the bottom left was erased because of damnatio memoriae.

Damnatio memoriae is a Latin practice or phrase that means "condemnation of memory". It means that a person's existence should be cut out of history. Actually, it was never totally achieved. In practice it meant removing the name from official records and monuments. That left plenty of letters and scrolls from which historians have pieced together the information we have.