The famous phrase those who are about to die salute you was never a gladiator tradition. According to the sources, it was recorded only once, screamed in unison by 19,000 condemned criminals on 100 warships before they slaughtered each other on a lake for the entertainment of the Emperor Claudius. In this episode we piece together the engineered, bloody world of the naumachia, ancient Rome's staged naval battles, and the artificial seas built to hold them.

We begin with Julius Caesar's 46 BC quadruple triumph and the basin near the Tiber filled with real warships dragged overland by enslaved labor, then Augustus in 2 BC, who built an even larger basin and an entire aqueduct, the Aqua Alsietina, to deliver undrinkable water to a murder show. We explore why cramped basins turned naval tactics into floating infantry brawls with no way to yield ...