Before the fifteenth century, the primary power sources for warships around the world were a combination of sails and oars. That is to say, they relied on both sails and rowing; when there was wind, they used sails, and when there was no wind, they used oars.
Between the fifteenth and sixteenth centuries, as human understanding of the oceans increased, they discovered that it was essentially impossible to encounter a complete lack of wind at sea. Even if there was no wind, warships could still navigate using ocean currents. Consequently, nations gradually abandoned oars, adopting sails as the sole source of power for their warships. By the mid-seventeenth century, sailing-powered warships had become the mainstream.
As warship propulsion evolved, naval combat tactics changed as well. During the Middle Ages (5th to 15th centuries AD), the primary naval weapon was the metal ram. Put simply, this involved mounting a sharp, protruding piece of metal onto the bow; upon encountering an enemy vessel, the ship would ram the enemy’s hull to cause structural damage, flooding, and eventual sinking. In addition to the metal ram, fleets employed long-range weapons like catapults and crossbows, as well as melee weapons such as spears, swords, and shields.
Chapter 718