His unusual name probably derives from the counts of Pardiac Bohemond was the second son of Bernard I of Astarac and the eldest by his second wife, Longuebrune.
In that year he went to war with Bernard de Marestaing, who was bribed by Longuebrune, by then prioress of Bolauc, not to burn Simorre.
In 1154 Bohemond had to borrow money from his mother in order to bribe Géraud d'Esparbès, the abbot of Saramon whom he had expelled, from plundering Astarac.
The couple donated property to the abbot of Berdoues in 1172, at which point they already had three children, all daughters: Mary, Marquese (Marchesia), and Bonnefemme (Bonefemina).
In March 1174 Bohemond approved the sale the castle of Lamaguère by its lord, Guillaume, to Géraud de la Barthe, Archbishop of Auch.