Though reputedly violent and dissolute, Drusus showed ability in public business. In AD 14 he suppressed a dangerous mutiny in Pannonia. He became consul in 15. As governor of Illyricum (17-20), he engineered the fall of Maroboduus, king of the German Marcomanni. After becoming consul again in 21, he received the administrative privileges of tribunician power in 22. He died before Tiberius, allegedly poisoned by his wife Livilla and by Tiberius' adviser Sejanus.
(Encyclopedia Britannica)
Only son of the Roman emperor Tiberius. After the death of Tiberius' nephew and adoptive son Germanicus (AD 19), Drusus became heir to the imperial succession.