Plate armour
Effect on weapon development

Plate armour gave the wearer very good protection against sword cuts, as well against spear thrusts, and provided decent defense against blunt weapons.

The evolution of plate armour also triggered developments in the design of offensive weapons. While this armour was effective against cuts or strikes, their weak points could be exploited by thrusting weapons, such as estocs, poleaxes, and halberds. The effect of arrows and bolts is still a point of contention with regard to plate armour. 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 pollaxes (poleaxes) were used to inflict blunt force trauma through armour. Strong blows to the head could result in concussion, even if the armour is not penetrated.

Fluted plate was not only decorative, but also reinforced the plate against bending under striking or blunt impact. This offsets against the tendency for flutes to catch piercing blows. In armoured techniques taught in the German 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 gussets, which were 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 the addition of couters and poleyns with "wings" to protect the inside of the joint.
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