Son of emperor John II Komnenos, Manuel I stands out for his 'Latinophile' attitude, imitating the western way of life. He also sought to appease the Turks. During his reign, he faced the Second Crusade, and a coalition of Normans, Serbs, Hungarians, and Kievans. His meddling in the West, such as the invasion of Italy and support for the Lombard League caused tension and his relations with Venice worsened. Manuel suffered a defeat at the hands of the Turks at Myriokephalon.

Manuel decided to stop restoring the aqueduct in Valens due to its irreversible neglience.