Armand de Périgord, also known as Hermann de Pierre-Grosse, was a descendant of the Counts of Périgord and a Grand Master of the Knights Templar.
He was master of the Province of Apulia and Sicily from 1205 to 1232. In 1232, he was elected Grand Master of the Templars. He organized attacks on Cana, Safita, and Sephoria, and against the Muslim positions around the Sea of Galilee. All of these expeditions were failures and diminished the Templars' effectiveness.
In 1236, on the border between Syria and Cilicia, 120 knights, along with some archers and Turcopoles, were ambushed near the town of Darbsâk (Terbezek). In the first phase of the battle, the Templars reached the town but they met fierce resistance. When reinforcements from Aleppo arrived, the Templars were massacred. Fewer than twenty of them returned to their castle in Bagras, fifteen km from the battle.
In September 1239, Armand arrived at Acre. He made a treaty with Sultan of Damascus, in parallel with the Hospitaller treaty with the Sultan of Egypt. In 1244 the Sultan of Damascus demanded that the Templars help repel the Khwarezmians from Asia Minor. In October 1244, the Templars, Hospitallers and Teutonic Knights, together with the Sultan of Damas, confronted with Sultan of Egypt and his Khwarezmian allies at the Battle of La Forbie. The Christian-Muslim coalition was defeated, with more then 30,000 deaths. Some Templars and Hospitallers reached Ascalon, still in Christian hands. Armand de Périgord may have been killed during the battle, but may have been captured and survived until 1247.