In Catilinam I-IV

The Catiline or Catilinarian Orations is a set of speeches to the Roman Senate given in 63 BC by Marcus Tullius Cicero, one of the year's consuls, accusing Lucius Sergius Catilina (Catiline) of leading a plot to overthrow the Roman government. Some modern historians, and ancient sources such as Sallust, suggest that Catiline was a more complex and sympathetic character than Cicero's writings declare, and that Cicero, a career politician, was heavily influenced by a desire to establish decisively a lasting reputation as a great Roman patriot and statesman. Most accounts of the events come from Cicero himself. This is one of the best, if not the very best, documented events surviving from the ancient world, and has set the stage for classic political struggles pitting state security against civil liberties.

Running for the consulship for a second time after having lost at the first attempt, Catiline was an advocate for the poor, calling for the cancellation of debts and land redistribution. There was apparently substantial evidence that he had bribed numerous senators to vote for him and engaged in other unethical conduct related to the election (such behaviour was, however, hardly unknown in the late Republic). Cicero, in indignation, issued a law prohibiting such machinations, and it seemed obvious to all that the law was directed at Catiline. Catiline, therefore, so Cicero claimed, conspired to murder himself and other key senators on the day of the election, in what became known as the Second Catilinarian conspiracy. Cicero announced that he had discovered the plan, and postponed the election to give the Senate time to discuss this supposed coup d'état.

The day after that originally scheduled for the election, Cicero addressed the Senate on the matter, and Catiline's reaction was immediate and violent. In response to Catiline's behavior, the Senate issued a senatus consultum ultimum, a declaration of martial law. Ordinary law was suspended, and Cicero, as consul, was invested with absolute power.

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