Caesar went out of his way for Marcus Junius Brutus (also known as Quintus Servilius Caepio Brutus), sparing Brutus after he had stood against Caesar and with his rival Pompey at Pharsalus, and then choosing him as praetor for 44. In Shakespeare's Julius Caesar, Caesar resolves to die only when he sees that even Brutus is against him. One explanation for this preferential behavior is that Caesar might have been Brutus's father.
Caesar had a passionate and long-term affair with the mother of Brutus, Servilia, the maternal half-sister of Cato, conservative senator and bitter personal enemy of Caesar. Cicero calls her "the warm friend and perhaps mistress of Caesar" in one of his letters to his pal Atticus. Brutus was proud of his anti-monarchic family heritage, a descendant of the famous Junius Brutus, who helped kick out the kings of Rome. But Servilia bore such ancestry, too; as Plutarch recounts in his Life of Brutus, "Servilia, the mother of Brutus, traced her lineage back to Servilius Ahala," who killed Spurius Maelius "who was seditiously plotting to usurp absolute power."
Once, when Caesar and Cato were in a knock-down, drag-out fight in the Senate, "a little note was brought in from outside to Caesar," according to Plutarch's Life of Cato the Younger. Cato figured that Caesar was involved in some conspiracy and demanded that the note be read aloud; making things really awkward, the piece of paper turned out to contain a love letter to Caesar from Servilia! Cato threw the letter at Caesar and just kept on talking.
Was Brutus the Son of Caesar?
Could Caesar have sired a son during his affair with Servilia? Possibly. It is objected that Caesar would have only been fifteen at the time Brutus was born, although this hardly precludes the possibility. If Caesar was his dad, that would make Brutus an even worse criminal than he already was, since he'd have committed patricide, one of the most awful deeds possible. Still, most scholars discount the idea that Caesar was Brutus's father.
Writing around 110 A.D., Plutarch does not clearly resolve the issue, but he does explain why Caesar may have considered Brutus his son. The fifth paragraph from Plutarch's Life of Brutus, on the paternity issue, contains a related, famous anecdote simultaneously showing Caesar besting Brutus' uncle Cato and also how enduring Caesar's relationship with Brutus's mother was.
And this he is believed to have done out of a tenderness to Servilia, the mother of Brutus; for Caesar had, it seems, in his youth been very intimate with her, and she passionately in love with him; and, considering that Brutus was born about that time in which their loves were at the highest, Caesar had a belief that he was his own child. The story is told, that when the great question of the conspiracy of Catiline, which had like to have been the destruction of the commonwealth, was debated in the senate, Cato and Caesar were both standing up, contending together on the decision to be come to; at which time a little note was delivered to Caesar from without, which he took and read silently to himself. Upon this, Cato cried out aloud, and accused Caesar of holding correspondence with and receiving letters from the enemies of the commonwealth; and when many other senators exclaimed against it, Caesar delivered the note as he had received it to Cato, who reading it found it to be a love-letter from his own sister Servilia, and threw it back again to Caesar with the words, "Keep it, you drunkard," and returned to the subject of the debate. So public and notorious was Servilia's love to Caesar.
-Edited by Carly Silver