Drusus Julius Caesar, Roman politician (d. 23 AD)
Drusus Julius Caesar (14 BC – 14 September AD 23), was the son of Emperor Tiberius, and heir to the Roman Empire following the death of his adoptive brother Germanicus in AD 19.

He was born at Rome to a prominent branch of the gens Claudia, the son of Tiberius and his first wife, Vipsania Agrippina. His name at birth was Nero Claudius Drusus after his paternal uncle, Drusus the Elder. In AD 4, he assumed the name Julius Caesar following his father's adoption into the Julii by Augustus, and became Drusus Julius Caesar.

Drusus first entered politics with the office of quaestor in AD 10. His political career mirrored that of Germanicus, and he assumed all his offices at the same age as him. Following the model of Augustus, it was intended that the two would rule together. They were both popular, and many dedications have been found in their honor across Roman Italy. Cassius Dio calls him "Castor" in his Roman History, likening Drusus and Germanicus to the twins, Castor and Pollux, of Roman mythology.Drusus died suddenly 14 September 23, seemingly from natural causes. Ancient historians, such as Tacitus and Suetonius, claim he died amid a feud with the powerful Sejanus, Praetorian prefect of Rome. They allege that he had been murdered. In their account, Sejanus had seduced his wife Livilla, and with the help of a doctor she had poisoned Drusus. Despite the rumors, Tiberius did not suspect Sejanus and the two remained friends until Sejanus's fall from grace in 31.