At a young age, Manuel received the high court title of sebastos from his uncle, Emperor Manuel I Komnenos (). The Emperor was of an age with Manuel's father, and the two had grown up together. Manuel I cherished this friendship and would always be partial to Andronikos, even though the latter, like his own father, was a highly ambitious man who coveted the throne. His ambition, plotting with foreign powers, rumours of attempting to assassinate Manuel I, and above all his scandalous affair with his niece Eudokia (a daughter of the sebastokrator Andronikos) brought Manuel's father into trouble, and in 1155, he was imprisoned by the Emperor in the dungeons of the Great Palace of Constantinople. Manuel is first mentioned in the sources in 1164, when he helped his father escape his imprisonment. Andronikos fled to Galicia, but soon the Emperor pardoned him and allowed him to return to Constantinople.
