Geta was always in a place secondary to his older brother Lucius, the heir known as Caracalla. Perhaps due to this, the relations between the two were difficult from their early years. Conflicts were constant and often required the mediation of their mother. To appease his youngest son, Septimius Severus gave Geta the title of Augustus in 209. During the campaign against the Britons of the early 3rd century, the imperial propaganda publicized a happy family that shared the responsibilities of rule. Caracalla was his father's second in command, Julia Domna the trusted counsellor and Geta had administrative and bureaucratic duties. Truth was that the rivalry and antipathy between the brothers was far from being improved.
Regardless, the shared throne was not a success: the brothers argued about every decision, from law to political appointments. Later sources speculate about the desire of the two of splitting the empire in two halves. By the end of the year, the situation was unbearable. Caracalla tried to murder Geta during the festival of Saturnalia without success. Later in December he arranged a meeting with his brother in his mother's apartments, and had him murdered in her arms by centurions.
Following Geta's assassination, Caracalla damned his memory and ordered his name to be removed from all inscriptions. The now sole emperor also took the opportunity to get rid of his political enemies, on the grounds of conspiracy with the deceased. Contemporary sources refer to numbers of about 20,000 persons of both sexes killed and/or proscribed during this time.