This paper argues that Cambyses’ treatment of Psammenitus in Book 3 of Herodotus’ Histories constitutes the adaptation of a punishment recorded in the Old Persian text of the Bisotun inscription. By outlining a typology for the practice, the article demonstrates the primacy of a Persian source, and proposes a series of specific, programmatically significant alterations made by Herodotus in the constructi on of the punishment. The resulting episode represents a complex engagement with questions arising from the Persian invasion of Egypt both in the Histories and in the wider historical record concerning Cambyses’ legitimacy as Egyptian ruler.