Constantine V vs Romanos I Lekapenos

Constantine V convened the Council of Hieria, which formally condemned the veneration of icons as idolatry. This council established iconoclasm as official Byzantine Church doctrine, intensifying the religious controversy that divided the empire.

Following the Council of Hieria, Constantine V intensified persecution of icon venerators. Monks were imprisoned, executed, or forced to marry. Monasteries were confiscated and converted to barracks or secular use. This policy deepened the iconoclast schism.

Constantine V led nine major campaigns against the Bulgarian Empire, achieving several victories including the Battle of Marcellae (759) and the Battle of Anchialus (763). These campaigns temporarily weakened Bulgaria but did not destroy it.

Constantine V oversaw the restoration of the Aqueduct of Valens, which had been damaged by the Avars. The repaired aqueduct restored water supply to Constantinople, improving urban infrastructure and public health.

Constantine V died while on campaign against the Bulgars. His death occurred during a military expedition, and he was succeeded by his son Leo IV. His campaigns had temporarily checked Bulgarian expansion but left the empire exhausted.

Romanos I led successful campaigns against the Abbasid Caliphate, recapturing several fortresses in eastern Anatolia. His general John Kourkouas achieved notable victories, including the capture of Melitene in 934.

Romanos I Lekapenos, a naval admiral, was appointed co-emperor by the young Constantine VII. He gradually sidelined Constantine and became the de facto ruler. His rise marked the beginning of the Lekapenos dynasty's dominance.

Romanos I negotiated a peace treaty with Tsar Peter I of Bulgaria, ending decades of war. The treaty included a marriage alliance between Peter and Romanos' granddaughter Maria. This brought stability to the Balkan frontier.

Romanos I was overthrown by his own sons Stephen and Constantine, who forced him to become a monk. He was exiled to the island of Prote and died in 948. His sons were soon overthrown by Constantine VII.