Murmillo
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The murmillo (also sometimes spelled "mirmillo", "myrmillo", or "mirmillones" pl. murmillones) was a type of gladiator during the Roman Imperial age. The murmillo-class gladiator developed in the early Imperial period to replace the earlier Gallus-type gladiator, named after the warriors of Gaul (Latin: Gallus, lit. 'a Gaul'). As the Gauls inhabiting Italy had become well integrated with the Romans by the time of the reign (27 BCE to 14 CE) of Augustus, it became undesirable to portray them as enemy outsiders; the Gallus-class gladiator thus fell out of use.
The designation murmillo originated with the Greek word μορμύρος (mormyrus) for a type of fish - murmillo gladiators could wear a Gallic-model helmet incorporating fish-imagery.