Hail, Emperor! Those who are about to die salute you!
From Suetonius' The Twelve Caesars, Claudius 21. A salute and plea for mercy recorded on one occasion by naumachiarii–captives and criminals fated to die fighting during mock naval encounters. Later versions included a variant of "We who are about to die", and this translation is sometimes aided by changing the Latin to nos morituri te salutamus.
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