"In Verrem" ("Against Verres") is a series of speeches made by Cicero in 70 BC, during the corruption and extortion trial of Gaius Verres, the former governor of Sicily. The speeches, which were concurrent with Cicero's election to the aedileship, led to Cicero's public career.

During the civil war between the government and the outlaw Sulla (83–82 BC), Verres had been a junior officer in a Marian legion under Gaius Papirius Carbo. He saw the tides of the war shifting to Sulla, and so, Cicero alleged, went over to Sulla's lines bearing his legion's paychest.

Afterwards, he was protected to a degree by Sulla, and allowed to indulge a skill for gubernatorial extortion in Cilicia under the province's governor, Gnaeus Cornelius Dolabella in 81 BC. By 73 BC he had been placed as governor of Sicily, one of the key grain-producing provinces of the Republic (Egypt at this time was still an independent Hellenistic kingdom). In Sicily, Verres was alleged to have despoiled temples and used a number of national emergencies, including the Third Servile War, as cover for elaborate extortion plots.

At the same time, Marcus Tullius Cicero was an up-and-coming political figure. After defending Sextus Roscius of Ameria in 80 BC on a highly politically charged case of parricide, Cicero left for a voyage to Greece and Rhodes. There, he learned a new and less-strenuous form of oratory from Molon of Rhodes before rushing back into the political arena upon Sulla's death. Cicero would serve in Sicily in 75 BC as a quaestor, and in doing so made contacts with a number of Sicilian towns. In fact, a considerable portion of his clientele at the time came from Sicily, a link that would prove invaluable in 70 BC, when a deputation of Sicilians asked Cicero to level a prosecution against Verres for his alleged crimes on the island.

The first speech was the only one to be delivered in front of the praetor urbanus Manius Acilius Glabrio. In it, Cicero took advantage of the almost unconditional freedom to speak in court to demolish Verres' case.

Cicero touched very little on Verres' extortion crimes in Sicily in the first speech. Instead, he took a two-pronged approach, by both inflating the vanity of the all-senator jury and making the most of Verres' early character. The second prong concerned Verres' defence's attempts to keep the case from proceeding on technicalities.

Verres had secured the services of the finest orator of his day, Quintus Hortensius Hortalus for his defence. Immediately, both Verres and Hortensius realized that the court as composed under Glabrio was inhospitable to the defence, and began to try to derail the prosecution by procedural tricks that had the effect of delaying or prolonging the trial. This was done by first trying to place a similar prosecution on the docket, to take place before Verres' trial, one concerning a governor of Bithynia for extortion.

The point of the attempted derailment of the case hinged on Roman custom. At the time the case was being argued, the year was coming to a close and soon a number of public festivals (including one in honor of Pompey the Great) would commence. All work ceased on festival days, according to Roman customs, including any ongoing trials. Cicero alleged that Hortensius was hoping to draw the trial out long enough to run into the festival period before Cicero would have an opportunity to conclude his case, thereby making it impossible for Glabrio and the jury to deliver a verdict before the new year, when the magistrates were replaced with their newly elected successors.