"Petchenegs versus Byzantium"
Pecheneg and Byzantine Territories
GNU Free Documentation LicensePecheneg and Byzantine Territories - Credit: Briangotts, Wikipedia

In 1091, the Pechenegs moved to invade the Byzantine capital of Constantinople. Byzantine leader Alexios I Komnenos  formed an alliance with the Cuman tribe and successfully attacked the Pecheneg camp.

The Battle of Levounion destroyed the Pechenegs, those not killed being incorporated into the Byzantine Empire.