Beowulf was a Neocymek created during the Butlerian Jihad. His biggest appeal to Agamemnon was his skill and knowledge in thinking machine programs and programming -- thus making him an acceptable canidate to replace Barbarossa. Beowulf had found a way to create an instructional loop that places false recording into Omnious's watcheyes, allowing Titans to hold secret meetings against The Evermind.
During the later throws of Butlerian Jihad, Beowulf suffered brain damage dealt by Hecate. Even though the neo-cymek wasn't what he used to be, as an act of appreciation towards Beowulf, Agememnon allows Beowulf to continue fighting with them.
Appearance
Beowulf only appears in the novel The Machine Crusade.