Cleopatra's presence in Rome most likely had an effect on the events at the Lupercalia festival a month before Caesar's assassination. Antony attempted to place a royal diadem on Caesar's head, but the latter refused in what was most likely a staged performance, perhaps to gauge the Roman public's mood about accepting Hellenistic-style kingship. Cicero, who was present at the festival, mockingly asked where the diadem came from, an obvious reference to the Ptolemaic queen whom he abhorred. Caesar was assassinated on the Ides of March (15 March 44 BC), but Cleopatra stayed in Rome until about mid-April, in the vain hope of having Caesarion recognized as Caesar's heir. However, Caesar's will named his grandnephew Octavian as the primary heir, and Octavian arrived in Italy around the same time Cleopatra decided to depart for Egypt. A few months later, Cleopatra had Ptolemy XIV killed by poisoning, elevating her son Caesarion as her co-ruler.