The Roman Navy
The Roman navy was very much inferior, both in prestige and capability, to the Roman army. Before the First Punic War in 264 BC there was no Roman navy to speak of as all previous Roman war had been fought in Italy. But the war in Sicily against Carthage, a great naval power, forced Rome to quickly build a fleet and train sailors. The first few naval battles of the First Punic War were disasters for Rome, and it was not until the invention of the Corvus, a grappling engine which made it easier for Romans to board the Carthaginian vessels, that Rome was able to win the war. This meant that Rome could use her superior army in naval combat, and was a significant shift away from the tactics of all other navies at the time.
Rome was able to use her superior army in preference to her navy in most of the wars she fought afterwards. By the late Empire Roman control over the Mediterranean coast meant that there were no non-Roman navies to fight. Indeed, Rome's last major naval battle was fought between Romans, Octavian and Marc Antony, at Actium. However, she still maintained a large navy which patrolled not just the Mediterranean, but the various major rivers in the empire. Although the quality of the navy did degrade into the later imperial period, emperors such as Diocletian put significant effort into rebuilding the navy. The average estimate of manpower strength of the navy ranges from 50,000-100,000.
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