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
osts. 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
laced 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 prob-
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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—though 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 o
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 321