Trihemiolia

From the 4th century BC on, new types of oared warships appeared in the Mediterranean Sea, superseding the trireme and transforming naval warfare. Ships became increasingly larger and heavier, including some of the largest wooden ships ever constructed. These developments were spearheaded in the Hellenistic Near East, but also to a large extent shared by the naval powers of the Western Mediterranean, more specifically Carthage and the Roman Republic. While the wealthy successor kingdoms in the East built huge warships ("polyremes"), Carthage and Rome, in the intense naval antagonism during the Punic Wars, relied mostly on medium-sized vessels. At the same time, smaller naval powers employed an array of small and fast craft, which were also used by the ubiquitous pirates. Following the establishment of complete Roman hegemony in the Mediterranean after the Battle of Actium, the nascent Roman Empire faced no major naval threats. In the 1st century AD, the larger warships were retained only as flagships, and were gradually supplanted by the light liburnians until, by Late Antiquity, the knowledge of their construction had been lost.

Most of the warships of the era were distinguished by their names, which were compounds of a number and a suffix. Thus the English term quinquereme derives from Latin quinque-rēmis and has the Greek equivalent πεντ-ήρης. Both are compounds featuring a prefix meaning "five": Latin quinque, ancient Greek πέντε. The Roman suffix is from rēmus, "oar": "five-oar". As the vessel cannot have had only five oars, the word must be a figure of speech meaning something else. There are a number of possibilities. The -ηρης occurs only in suffix form, deriving from ἐρέσσειν, "to row". As "rower" is eretēs and "oar" is eretmon, -ērēs does not mean either of those but, being based on the verb, must mean "rowing". This meaning is no clearer than the Latin. Whatever the "five-oar" or the "five-row" originally meant was lost with knowledge of the construction, and is, from the 5th century on, a hotly debated issue. For the history of the interpretation efforts and current scholarly consensus, see below.

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