Caracalla (188-217) was a Roman emperor whose reign was characterized by cruelty in his private life and irresponsibility in his public life.
Son of Emperor Septimius Severus and his Syrian empress, Julia Domna, Caracalla was originally named Bassianus. His father renamed him Marcus Aurelius Antoninus in 196 (Severus pretended to have been adopted into the prestigious Antonine family of emperors), but the boy was commonly called Caracalla from a Gallic cloak he affected.
Caracalla was named caesar (successor-designate) by his father in 196 during Severus's struggle with his rival, Albinus. Two years later Caracalla was promoted to the rank of augustus, or coemperor. His younger brother, Geta, received the same rank in 209. Both boys were with their father in Britain when he died in 211, leaving them corulers of the empire. Caracalla straightway returned to Rome, where the long-standing animosity between the brothers led Caracalla in 212 to assassinate Geta as he cowered in his mother's arms. Those that indicated disapproval were executed, but Caracalla secured the loyalty of the troops by a donative and raise in pay.
Caracalla fancied himself a military genius, the reincarnation of Alexander the Great. In 213 he led an expedition against the Germanic Alamanni, who threatened the northern frontiers. He defeated some and bought off others, while completing permanent fortifications in the area. In 214 he campaigned on the Danube. Meanwhile, he raised a phalanx of Macedonian troops so that he could proceed on an expedition to the East, in perfect emulation of his great hero, Alexander.
Caracalla reached Antioch in Syria in 215. But his ambition to create a Romano-Iranian empire was at first thwarted by the reluctance of the Parthian king to quarrel. Caracalla thereupon made a trip to Alexandria, where, in his resentment at the citizens' traditional liberty of speech, he assembled the city's youth and had them massacred by the army.
In 216 Caracalla decided to join Rome and Parthia by marriage, if he could not do so by arms, and asked for the hand of the Parthian king's daughter. A refusal was followed by an ineffectual invasion of Media. The Emperor wintered at Edessa and was preparing a more vigorous campaign for the following season when, in the spring of 217, he was assassinated near Carrhae at the instigation of his praetorian prefect and successor, Macrinus, who had information that Caracalla was planning his execution.
Caracalla is best known for the baths he built in Rome, which carry his name, and for an edict in 212/213 which granted full Roman citizenship to nearly all the free inhabitants of the empire, thus fulfilling centuries of legal progress. Some see in this a reflection of Caracalla's ideal of a world state, but ancient authorities found the motivation in increased revenue: only Roman citizens paid an inheritance and manumission tax, and this tax was doubled at this time.
A discussion of Caracalla by S. N. Miller is in S. A. Cook and others, eds., Cambridge Ancient History, vol. 12 (1939). See also H. M. D. Parker, A History of the Roman World from A.D. 138 to 337 (1935; rev. ed. 1958).