These gigantic horse was used to carry knights with heavy armor and carry the heavy armor of their own. These horses weighed over 1000 pounds and were very tall and had a lot of muscle. Thats why they used them for this reason. They weren't very often killed in battle.
Esta es de las Cruzadas Albigenses. Gautier II (izquierda) y Bouchard I (derecha) observan como la vanguardia cruzada pasa a duras penas un río a las afueras de Avignon, que estaba siendo asediada. Más en www.elgrancapitan.org/foro