The conspiracy against Caesar likely festered for a long time, but it only began to take on a legitimate threat in the early part of 44 BC.
In a Senate famous for political wrangling and back-stabbing, a conspiracy of such grave magnitude could not have been kept secret for long. The urgency of the plot was not only the fact that Caesar was expected to leave Rome for Parthia on March 18, but that Caesar was expected to be named King of all the Roman provinces outside of Italy.
The apparent leader of the plot was Gaius Cassius Longinus, the Praetor Peregrinus in 44 BC. He already held a grudge against the dictator for perceived political slights, mainly in not backing him for positions of higher authority. In fact, Caesar seems to have had suspicions of Cassius already, but apparently did nothing to counteract it. Caesar often made comments regarding his own death by suggesting he would prefer to die one death than die countless times as a coward. On a similar note, Cicero once quoted Caesar as saying, "I have lived long enough both in years and in accomplishment."
