How did Leo III influence the military and religious policies of Constantine V?

Leo III significantly shaped the reign of his son, Constantine V, by instilling in him both his military tactics and his religious convictions.1

Military Influence

Leo III left the Byzantine army a more effective instrument than he had found it, having personally led troops in battle and reorganized the military-district armies (themes) to prevent commanders from seizing the throne. His victory over the Arabs at Akroïnos in 740 effectively secured Asia Minor from immediate threats, which directly enabled Constantine V to launch a forceful counteroffensive and reconquer lost territories. Constantine V continued to build upon this foundation, utilizing the stability and military improvements established by his father to conduct successful campaigns against the Arabs and, later, the Bulgars.12

Religious Influence

Leo III established Iconoclasm as the official imperial policy, a doctrine that rejected the use of religious images in worship. He successfully passed these Iconoclastic views on to Constantine V, who not only followed his father’s lead but intensified these policies during his own reign. This religious stance remained a source of deep division within the empire for a century.1