At the time, both Gradisca d'Isonzo and Trieste were an integral part of the Austro-Hungarian Empire, so his son Antonio was drafted into the Austrian army. In 1916 Antonio defected, fled to Italy and volunteered in the 137th Infantry Regiment of the Barletta Brigade under the name of Antonio Bontempelli, a false identity imposed by the Royal Italian Army to accommodate the irredentists among his ranks. While leading the attack of his platoon, during a fight at the foot of Monte Cimone di Tonezza, on 16 June 1916, Antonio was joined and killed by a barrage of machine gun. At the end of the battle, a note was found in his pockets in which he begged to inform the mayor of San Giovanni al Natisone, the only person aware of his real identity, of the death. The body of Antonio Bergamas was therefore recognized and buried along with the others who fell in the war cemetery of Marcesina on the Sette Comuni Plateau. However, following a violent bombing that destroyed the cemetery, Bergamas and the comrades who died with him were officially missing.