Battle of Cannae Hannibal at Cannae, with approximately 86,000 Roman and allied troops. They massed their heavy infantry in a deeper formation than usual, while Hannibal used the double-envelopment tactic and surrounded his enemy, trapping the majority of the Roman army, who were then slaughtered. The loss of life on the Roman side was one of the most lethal single day's fighting in history; Adrian Goldsworthy equates the death toll at Cannae to "the massed slaughter of the British Army on the first day of the Somme offensive in 1916." Only about 15,000 Romans, most of whom were from the garrisons of the
Romans in Persia of the dynasties in control of their empires in different historical periods: first were the Medians (Media Atropatene), then Parthians and finally Sassanians. In 64 BC Pompey conquered the remaining Seleucid territories in Syria, extinguishing their state and advancing the Roman eastern frontier to the Euphrates, where Romans met for the first time the territory of the Parthians. Mark Antony, in his quest to avenge the battle of Carrhae defeat, conquered in 33 BC some areas of Atropatene (northern Iran) and Armenia but soon lost it: that was the first time that Romans occupied a Persian territory, even if temporarily.