Gaumata

Gaumata/Smerdis/Sphendadates
Predecessor	Cambyses II
Successor	Darius I
Burial	522 BCE
Dynasty	Achaemenid Empire

Gaumata () or False Smerdis (ψευδὴς Σμέρδις) or Sphendadates (Σφενδαδάτης) (and various other names and aliases) appears in epigraphical and historiographical sources of classical antiquity as a late-6th century BCE Mede who usurped the Achaemenid throne by impersonating a member of the ruling family. The usurper is named 'Gaumata' in the Behistun inscription of Darius I, named '(false) Smerdis' in Herodotus' Histories, and is named 'Sphendadates' in the surviving fragments of Ctesias. Other sources have other names.

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