Around the eighth century B.C. two banked warships are put into common use by the Greek navy. There are many references to them in literature, as well as visual depictions, so their existence is not disputed. What is of dispute though, is to how they are referred, e.g., a two level pentecontor. Thus in translation, a two level pentecontor would be a two level, fifty oared ship. It seems that this would be the case, as it would create a shorter, thus more maneuverable ship, while retaining the power of fifty oarsmen.
Greater controversy exists involving the oarsmen of the Greek trireme.
Put to use in the sixth century B.C., the trireme became the standard by which warship design was based in the Mediterranean for centuries. There are two main schools of thought involving the placement of oarsmen on the trireme. The first is that the oars were worked from three separate levels, and to each oar, a single oarsman. This number seems well within reason, and would create a powerful and well maneuverable vessel. The second school of thought involves a ship not of three levels, but a single level ship with three men to an oar.