The Surcoat originated as an important identifying part of the medieval knight’s battlefield dress. It was a long garment worn above all the armour and dress of the knight. The specific purpose it served was to identify the knight on the battlefield.
Usually, each knight had a surcoat carrying his own coat of arms, although sometimes an entire army would wear the surcoats of the same colour such as was the case during the Crusades. According to some historians, it was the identifying marks on the surcoats which ultimately led to the development of heraldry all over medieval Europe.
The earliest recorded instance of the use of surcoat was in the 12th century. According to historical sources, around this time the medieval European knights began wearing surcoats which fell all the way to their midcalf. Like the hauberk, the surcoats were worn with slits in the front and the back which allowed the wearer to mount or dismount the horse easily.
These surcoats carried symbols of the respective arms of each knight so that despite the use of armour such as great helm which completely hid the knight’s face, he could be identified by his fellow knights on the battlefield. The surcoat became shorter in size towards the 14th century. By the 15th century, it had been replaced by another identifying garment called the jupon.
The surcoat began to be worn by the knights during the 12th century. It became an important part of a knight’s identity on the battlefield since due to heavy armour, it was virtually impossible to identify him otherwise. The identification symbol which the knights used on their surcoats later led to the development of standard coat of arms.
It is believed that this is the origin of the heraldry in medieval Europe and that once too many knights began using the symbols of their arms on their surcoats, it became important to regulate it whereby the courtly institutions of heraldry were created.
Before the development of the standard full-body plate armour, an interesting type of armour emerged in the 13th century. This kind of armour was directly linked to the surcoat and was called the coat of plates. It essentially utilised the standard surcoat in which were sewn or attached a large number of metal plates.
Such a surcoat then essentially served as a metal armour with a padded exterior which could be used both for the protection of the knight’s body and to identify him through the arms emblazoned on the exterior.
Since the beginning of its use in the 12th century, one of the major problems with wearing a surcoat was its size. Due to the fact that it was usually a flowing and long garment, it was inconvenient to wear it in rain, muddy terrain or when on foot. This was the key factor which drove the evolution of the surcoat and ultimately led to its decline.
The use of surcoat declined in 14th century when a shorter garment which was easier to wear and carry called a jupon became a popular replacement for it. By the 15th century, the surcoat had been entirely phased out.