Plate armour: is a historical type of personal armour made from iron orsteel plates. While there are early predecessors such the Roman-eralorica segmentata, full plate armor developed in Europe during the Late Middle Ages, especially in the context of the Hundred Years' War, from thecoat of plates worn over mail suits during the 13th century. In Europe platearmour reached its peak in the late 15th and 16th centuries, with the full suits of Gothic plate armour worn on the battlefields of the Burgundian andItalian Wars. The most heavily armoured troops of the period were heavy cavalry such as the gendarmes and early cuirassiers, but the infantry troops of the Swiss mercenaries and the landsknechts also took to wearing lighter suits of "three quarters" plate armor, leaving the lower legs unprotected.
The use of plate armour declined in the 17th century, but remained common both among the nobility and for the cuirassiers throughout theEuropean wars of religion. After 1650, plate armour was mostly reduced to the simple breastplate (cuirass) worn by dragoons. This was due to the development of the flintlock musket which could penetrate armour at a considerable distance, severely reducing the payoff from the investment in full plate armour.
For infantry, the breastplate gained renewed importance with the development of shrapnel in the late 18th century. The use of steel plates sewn into flak jacket dates to World War II, replaced by more modern materials such as fibre-reinforced plastic since the 1950s.
It is a common misconception that the plate armours of European soldiers adversely affected mobility in a significant manner, but in fact plate armor was less heavy and with the weight more evenly distributed than for a modern firefighter wearing oxygen gear.
Effect on weapon development
Plate armour was virtually invulnerable to sword slashes. It also protects the wearer well against spear or pike thrusts and provides decent defence against blunt trauma.
The evolution of plate armour also triggered developments in the design of offensive weapons. While this armour was effective against cuts or blows, their weak points could be exploited by long tapered swords or other weapons designed for the purpose, such as poleaxes and halberds.
The effect of arrows and bolts is still a point of contention in regards to plate armour. Longbows and crossbows could also pierce plate armour up to ranges of 200 metres (660 ft) with a lucky shot, notably in battles such as the Battle of Visby, though historian Jean Froissart suggests that the success of such weapons at the Battle of Poitiers was less due to thebodkin arrows used by the English and more due to aiming for the side or rear of the armour, which is weaker.
The evolution of the 14th-century plate armour also triggered the development of various polearms. They were designed to deliver a strong impact and concentrate energy on a small area and cause damage through the plate. Maces, war hammers and the hammer-heads of pollaxes (poleaxes) were used to inflict blunt trauma through armour.
Fluted plate was not only decorative, but also reinforced the plate against bending under slashing or blunt impact. This offsets against the tendency for flutes to catch piercing blows. In armoured techniques taught in theGerman school of swordsmanship, the attacker concentrates on these "weak spots", resulting in a fighting style very different from unarmoured sword-fighting. Because of this weakness most warriors wore a mail shirt (haubergeon or hauberk) beneath their plate armour (or coat-of-plates). Later, full mail shirts were replaced with mail patches, called goussets, sewn onto a gambeson or arming jacket. Further protection for plate armour was the use of small round plates called besagews that covered the armpit area and couters and poleyns with "wings" to protect the inside of the joint.