=Cæ´sar.= A surname given to the Julian family in Rome. This name, after it had been dignified in the person of Julius Cæsar and his successors, was given to the apparent heir of the empire in the age of the Roman emperors. The first twelve emperors were distinguished by the name of Cæsar. They reigned in this order--Julius Cæsar, Augustus, Tiberius, Caligula, Claudius, Nero, Galba, Otho, Vitellius, Vespasian, Titus, and Domitian. Suetonius has written an exhaustive history of the Cæsars. C. Julius Cæsar, the first emperor of Rome, was son of L. Cæsar and Aurelia, the daughter of Cotta. He was descended, according to some accounts, from Julus, the son of Æneas. His eloquence procured him friends at Rome, and the generous manner in which he lived equally served to promote his interest. He was appointed for five years over the Gauls. Here he enlarged the boundaries of the Roman empire by conquest, and invaded Britain, which till then was unknown to the Romans. The corrupt state of the Roman senate, and the ambition of Cæsar and Pompey, caused a civil war. Neither of these celebrated Romans would endure a superior, and the smallest matters were grounds enough for unsheathing the sword. By the influence of Pompey a decree was passed to strip Cæsar of his power. Antony, as tribune, opposed this, and went to Cæsar's camp with the news. On this Cæsar crossed the Rubicon, which was the boundary of his province. The passage of the Rubicon was a declaration of war, and Cæsar entered Italy with his army. Upon this Pompey left Rome and retired to Dyrrachium, and Cæsar shortly afterwards entered Rome. He then went to Spain, where he conquered the partisans of Pompey, and on his return to Rome was declared dictator, and soon afterwards consul. The two hostile generals met in the plains of Pharsalia, and a great battle ensued B.C. 48. Pompey was defeated and fled to Egypt, where he was slain. At length Cæsar's glory came to an end. Enemies had sprung up around him, and a conspiracy, consisting of many influential Romans, was formed against him. Conspicuous among the conspirators was Brutus, his most intimate friend, who, with others, assassinated him in the senate house in the ides of March, B.C. 44, in the fifty-sixth year of his age. He wrote his Commentaries on the Gallic wars when the battles were fought. This work is admired for its elegance and purity of style. It was after his conquest over Pharnaces, king of Pontus, that he made use of the words, which have since become proverbial, _Veni, vidi, vici_, illustrative of the activity of his operations. Shakspeare's tragedy of Julius Cæsar, in the third act of which he is assassinated, uttering as his last words, "_Et tu, Brute!_ Then fall Cæsar"--is devoted to the conspiracy and its results, ending with defeat and death of Brutus and Cassius at Philippi.