Though not really either yay or nay over the idea of naval warfare being introduced, I'll just add a post explaining a little about warfare in medieval times. Appologies in advance for not having time for much editing
Medieval naval warfare
OUTLINE HISTORY
The two main scenes of action for medieval European naval warfare were the Mediterranean and the North Sea/English Channel. Conflicts between fleets were relatively few. Such as did occur were usually over transporting troops and supplies for war, or the domination of trade routes. Much medieval naval conflict had to do with illicit action by pirates—a plague to all sides though states often encouraged privateering. In the Mediterranean, the focus was on islands and ports on major routes. Attempts to clear out pirate bases, as at Rhodes, Sapienza or the Barbary Coast, were another type of conflict. Channel warfare was mostly over trade, as when England fought Flanders over wool and cloth, and France over wine. The wars between Venice and Genoa were about control of trade to the Middle and Far East. Fishing grounds also caused conflict.
State fleets were rare and usually small, supplemented in war by mercantile shipping. Ships involved in naval warfare were hardly different from those used for trade. In the later Middle Ages naval powers built more ships as the expense of large warships became too great for private enterprise. We do find some large fleets. In 1347 Edward III crossed the Channel with 738 ships carrying 32,000 men to Calais.
The Romans and others produced ships designed for war, a tradition continued by the Byzantines. They had underwater rams to hit below water level and sink ships. This was not a major feature in medieval warfare, where the projecting bow became higher from at least the 10th century, making a beak rather than a ram, with the aim of boarding rather than sinking. Outside the Mediterranean early ships were usually clinker built, that is with overlapping planks nailed together. They were also partly propelled by oars. Viking ships were clinker built and normally had a single sail. Early northern ships were usually built upwards from the keel.
A major medieval contribution to naval warfare was the Byzantine invention of Greek Fire, generally shot from a siphon. The exact ingredients remain unknown but its effect was to ignite on impact—clearly effective against the hulls and sails of medieval ships. It was perhaps the chief reason that Constantinople remained free of capture for so long. Eventually the west and the Turks learned how to use Greek Fire.
The main medieval developments were in shipbuilding and navigational knowledge. Ships became larger, useful for carrying larger cargoes but also for war. Larger ships, known as cogs, were made through working on a frame, with straight stem and stern posts. The frames were filled in with flush planks rather than overlapping. They had rounder hulls. The mast (now larger) was stepped, making it firmer, and was generally placed more forward. From the 13th century one finds fixed decking. Caulking material and varnish have been found in underwater excavation. There was a move from a side to a rear rudder, though this did not necessarily improve manoeuvrability.
One development largely concerned with conflict was the heightening of structures at prow and/or stern to make castles. At first these were added to an existing hull, but by the 14th century they were part of the original structure. In conflict this favoured the use of missile weapons especially by archers. Fighting tops were also built on the masts.
In the later Middle Ages the larger ships, found in the Mediterranean and the North Sea, were called carracks. They usually had two and later three masts. In 1420 the English royal fleet had 13 ships with two masts. By the end of the century three masts were normal with a mainsail, foresail and lateen mizzen. By this time spritsails and topsails were also common. The larger vessels could carry larger crews and more guns, giving further advantage in conflict. The added sails made for greater manoeuvrability than galleys.
Galleys remained important in the Mediterranean throughout the Middle Ages. Oarsmen had the advantage of being able to manoeuvre and move quickly. The problem was a low draft that could mean flooding of the ship in bad weather and was impractical in the North Sea. In the later Middle Ages larger great galleys appeared with higher hulls, relying more on sails than oars athough having both. In the Mediterranean the advantage was mostly with the Christian powers. As Pryor has argued, this was because of weather conditions, winds and currents, giving advantage to those sailing from the north, allowing northern powers to control major ports and routes. The Italian sea powers took the lead in shipbuilding from the 11th century. Control of the sea prolonged the existence of the crusading states. Western domination was only threatened when the Arabs controlled the major islands in the early Middle Ages, and when the Ottomans controlled much of eastern Europe in the 15th century.
Christian domination did not necessarily mean peace, and one of the most enduring naval conflicts of the Middle Ages was the struggle between the trade rivals from Italy—Venice and Genoa. North Sea warfare was dominated by the Vikings in the early Middle Ages though Medieval naval warfare their domination was such that warfare was rare and gave them the opportunity to raid and settle. Opposition came mainly on land. The Normans, under rulers descended from the Vikings, also utilised naval power to invade England and Sicily. In the Hundred Years’ War England had the advantage over France in the Channel through much of the war following the early victory at Sluys.
At the end of the Middle Ages, navigational development made longer voyages easier. It is true that the Vikings had made remarkable voyages to Iceland, Greenland and North America but they did so with considerable danger.
By the later Middle Ages, there were larger ships, better able to cope with oceanic conditions. Compasses, quadrants, astrolabes, globes and better knowledge of the heavens and the earth were available. There were capstans, pumps, bigger anchors and equipment for deep sounding. Iberia in particular took early advantage to make longer voyages and begin a new history of colonisation. Spain and Portugal were ideally placed to learn from Mediterranean and Channel developments and pioneered large ocean-going ships in the 15th century, often called caravels. They won control of much of the Mediterranean and pushed ahead with long-distance voyages round Africa and across the Atlantic.
