Kingdom Of Heaven - 20th Century Fox
A gambeson (or aketon) is a padded defensive surcoat, worn as armour separately, or combined with mail or plate armour. Gambeson were produced with a sewing technique called quilting. Usually constructed of linen or wool, the stuffing varied, and could be for example scrap cloth or horse hair. During the 14th century, illustrations usually show buttons or laces up the front.

The gambeson was used both as a complete armour unto itself and underneath mail and plate in order to cushion the body and prevent chafing. It was very insulatory and thus uncomfortable, but its protection was vital for the soldier.

For common soldiers who could not afford mail or plate armour, the gambeson, combined with a helmet as the only additional protection, remained a common sight on European battlefields during the entire Middle Ages, and its decline came only with the Renaissance, just like for plate armour due to the rising importance of firearms, and by the 17th century, it was no longer in military use.