20. Cn.CalpurniusPiso, was a young noble who had dissipated his fortune by his extravagance and profligacy, and being a man of a most daring and unscrupulous character, attempted to improve his circumstances by a revolution in the state. He therefore formed with Catiline, in B. C. 66, a conspiracy to murder the new consuls when they entered upon their office on the 1st of January in the following year. The history of this conspiracy, and the manner in which it failed, are related elsewhere. [CATILINA, p. 629b.] Although no doubt was entertained of the existence of the conspiracy, still there were not sufficient proofs to convict the parties, and they were not therefore brought to trial. It had been arranged by the conspirators, that after the murder of the consuls, Piso was to be despatched, with an army, to seize the Spains; and the senate, in order to get rid of this dangerous agitator, now sent him into Nearer Spain as quaestor, but with the rank and title of propraetor. By his removal the senate hoped to weaken his faction at Rome, and they gave him an opportunity of acquiring, by the plunder of the province, the money of which he was so much in need. His exactions, however, in the province soon made him so hateful to the inhabitants, that he was nurdered by them. Some persons, however, supposed that he was murdered at the instigation of Pompey, who had possessed great influence in the country ever since the conquest of Sertorius. Crassus had been in favour of sending Piso to Spain, that he might, by Piso's means, persecute the friends of his great enemy and rival, Pompey; and it was therefore thought that the latter had revenged himself, by making away with the new governor. (D. C. 36.27; Sal. Cat. 18, 19; Cic. pro Sall. 24, pro Mur. 38 ; Ascon. in Cornel. p. 66, in Tog. Caml. pp. 83, 94.)