This article is an attempt to examine the tradition of tyrannicide and republican liberty in William Shakespeare’s Julius Caesar. Studies have so far showed that Shakespeare’s political intentions in this work are hard to capture. However, Shakespeare wrote this play as part of rediscovering classics, which was prevalent during and after the Renaissance. In late medieval and early modern European countries, the rediscovery of ancient Greek and Latin texts entails a movement to reclaim and apply to the real world of politics the principles of the Roman republic represented by Cicero. Shakespeare emulated this trend and demonstrated the Roman understanding of republican freedom through Brutus who killed Caesar. Praised as the most noble Roman, Brutus inherited the Greek tradition of tyrannicide, which was handed down to Rome and became the theoretical basis for modern revolutions including the American Revolution. Nowadays, Pettit and others insist on recuperating the republican conception of freedom as shown in the case of Brutus.