The Caesar who was preparing to face the Ides of March was now at the height of his power. After triumphing over his Pompeian enemies, the fifty-five-year-old dictator was preparing an unspecified constitutional reform of the Res Publica, presumably of a monarchical nature. He was also preparing new campaigns against the Parthians in the East and the Germanic peoples.

However, these ambitious plans would ultimately be thwarted by his imminent assassination.

Given Caesar's significance and political legacy, it was predictable that tales of omens and warnings would arise. Two years after his death, he was deified, so stories about the future divus Julius's demise naturally acquired paranormal overtones. Reports include visions of will-o'-the-wisps, solitary birds in the Forum, and unsettling nocturnal noises. As Pontifex Maximus, Caesar was said to have performed a sacrifice in which the victim's heart could not be found, considered an ominous sign.

The most notable warnings came from Spurinna, the Etruscan soothsayer, and Caesar's wife, Calpurnia. Spurinna advised him to beware the Ides of March and repeated this before Caesar entered the curia. Calpurnia dreamed of their house collapsing and her husband lying dead. Capys, mythical founder of Capua, was also cited: during demolition by Caesar's colonists, his tomb was unearthed, bearing a bronze slab that predicted that a descendant of Iulus would be murdered by his kin and soon avenged with slaughter and mourning for Italy. This referred to Marcus Junius Brutus, Caesar's assassin, and rumours that he was Caesar's illegitimate son.

Despite his known Epicurean sympathies, Caesar was likely influenced by these omens and decided to stay and postpone the March 15 session. However, that same morning, Decimus Brutus—his lieutenant in Gaul and a conspirator—reached him and persuaded him to attend, arguing that his absence could be seen as disrespect towards the Senate.