Needing a bomber that could reach the German industrial works at Essen, Germany, the French selected the Bréguet Br.M5 from an air competition held in October 1915. Produced in two versions, the 4B.2 had a Hotchkiss or Lewis machine gun mounted in front and Michelin bomb racks mounted on the lower wings. The second version, a bomber escort, was the 5Ca.2. In addition to a machine gun up front, the 5Ca.2 had a fixed machine gun mounted to the top wing. This second machine gun was rear-firing and was replaced with another gun when it proved to be of little or no value in combat.
The Bréguet Br.M5 soon demonstrated that it was too slow and vulnerable for daylight bombing and offered poor visibility from the cockpit for bombing at night. Less than a year after it was introduced, the Bréguet Br.M5 was withdrawn from combat and replaced with newer aircraft like the Voisin 8.