Caracalla's reign was marked by two notable incidents. The so-called "Antoninian Constitution" gave Roman citizenship to all free people of the provinces. This was a trend that had been leading up to this time rather than a bold new decree. Ironically, Caracalla alienated many of the new citizens when he massacred a large number of Egyptian celebratory in Alexandria. In 213, Caracalla scored major military victories along the Rhine border. Then in 214, he idolised himself as the military hero Alexander the Great and sought to retrace his footsteps by attacking the Parthians. The Parthians who where in the midst of a civil war initially acquiesced to Caracalla's demands. However, Caracalla simply made more egocentric demands and invaded Parthia in 216 anyway. He reached Media before finally being murdered by the leader of the Praetorian Guard, Marcus Opellius Macrinus.