Gaius Caesar - Caesar of Imperium Romanum from 17 BC to 4 AD
Gaius Caesar was consul in AD 1 and the grandson of Augustus, the first emperor of the Roman Empire. Although he was born to Marcus Vipsanius Agrippa and Julia the Elder, Augustus' only daughter, Gaius and his younger brother, Lucius Caesar were raised by their grandfather as his adopted sons and joint-heirs to the empire.

He would experience an accelerated political career befitting a member of the Julio-Claudian dynasty, with the Roman Senate allowing him to advance his career without first holding a questorship or praetorship, offices that ordinary senators were required to hold as part of the cursus honorum.

In 1 BC Gaius was given command of the eastern provinces, after which he concluded a peace treaty with King Phraates V of Parthia on an island in the Euphrates. Shortly afterward, he was appointed to the office of consul the following year in AD 1. The year after Gaius' consulship, Lucius died at Massilia in the month of August. Approximately eighteen months later, Gaius died of an illness in Lycia. He was married to his second cousin Livilla but they did not have children.
Gaius Caesar
Caesar Gaius Caesar of the Roman Empire

Obverse: laureate head right; AVGVSTVS__DIVI•F
Reverse: Caius Caesar on horseback riding right, holding sword and reins; to left, aquila right between two signa; C•CAESAR / AVGVS•F
Ref: RIC I 199, BMCRE I 500, RSC I 40
Obverse: laureate head right; CAESAR AVGVSTVS__DIVI F PATER PATRIAE
Reverse: Lucius Caesar and Caius Caesar facing, wearing toga, holding shield on the ground and spear, simpulum and lituus (b9) above; AVGVSTI F COS DESIG PRINC IVVENT / C L CAESARES
Ref: RIC I 207, RSC I 43, BMCRE I 533, B...
Obverse: CAESAR AVGVSTVS DIVI F PATER PATRIAE, Head of Augustus facing right, wearing laurel wreath
Reverse: C L CAESARES AVGVSTI F COS DESIG PRINC IVVENT, Gaius and Lucius Caesar standing, each, wearing togas, resting hand on shield and spear, simpulum, right, and lituus, left, flanking, left and right respectively
Ref: RIC I (2nd Ed.) Augustus 207
AE Half-Unit Pergamum
Obverse: ΓΑΙΟΝ ΚΕΦΑΛΙΩΝ, Bare head of Gaius facing right
Reverse: ΛΕVΚΙΩΝ, Bare head of Lucius facing right
Ref: RPC I 2363