The war against Mithridates and the civil war between Marina and Salta followed. The first Mithridatio war lasted from B.C.87 to s.c. 84. After its conclusion Sulla returned to Italy, forced his way to Rome, and was made perpetual dictator (ac. 82). In me. 83 the second Ilithridatie war broke out, in which the Romans were defeated, and in ac. 81 they concluded a peace. In ex, 74 Mithridates commenced the third war against the Romans, which led to the complete subju gation of all Asia Minor, Syria, and Pbcanicia. Other Roman generals in the meantime advanced into Maisie as far as the Danube, and on the northern coast of the Euxine as far as the river Don and the Pales Mmotie, or Sea of Aut. In ac. 63 Rome was saved by the watchful care of Cicero from the destruction with which the con spiracy of Catiline threatened it. Between s.o. 58 and B.C. 50 Caesar completed the conquest of Gaul ; and In B.C.56, by the treaty of Lucca, the Roman world wu divided among Caesar, Creams, and Pompey (first triumvirate); and when Pompey, as sole consul (a.c. 52), placed himself at the head of the republic, the civil war between him and Caesar broke out which was decided In B.C. 48 by the battle of Phar salus. ,Cesar, who bad now become dictator, defeated the remains of the Pompeian party, and then endeavoured to restore order in Italy; but he was assassinated in &C. 44. His opponents, whose republican spirit bad survived the republic, were unable to restore it ; and in the following year a second triumvirate was formed by Octavianus, Antony, and Lepidus, whose object was the total destruction of the republican party. This object they pursued by proscriptions and a aeries of despotic and cruel measures, until began to quarrel with one another. Their quarrels led to a new war, which ended in the battle of Actium, and placed Octavianus (Augustus) at the head of the Roman world. Thus ended the Roman republic.
The Roman republic at the time of its dissolution comprehended the following countries which were for the most part administered as Roman provinces and all the islands by which it was rounded; all Gaul as far as the Rhine ; nearly all Spain, Illyricum, Pannonia, Dalmatia, Greece with all the islands of the iEgean, Thrace, Mcesia (the Danube here formed the boundary): in Asia all tho countries between the Caspian Sea, the Parthian empire, the Persian and Arabian gulfs, the Mediterranean and the Caucasus, that is, Colchis, Iberia, Armenia, Syria, Palestine, Phoenicia, nearly the whole of Asia Minor, the whole of the northern coast of Africa, Mauritania, Nnmidia, the territory of Carthage, Cyrenalca, and Egypt. In some of these countries however the power of Rome was not firmly established until the imperial period.
The imperial period comprises the interval from the accession of Augustus to the deposition of Romulus Augustulus, that is, from B.C. 30 to A.D. 476.
Augustus gradually concentrated in his own person all the great offices of the republic, though the officers themselves, mere shadows of former days, still continued to be appointed. He thus in effect acquired the sovereign power, being free from all responsibility. He had the right to raise armies, to impose taxes, to decide on peace and war; he had the command of all the legions, and the power of life and death over all Roman citizens, both within and without the city. The
senate, after the removal of those whom Augustus had reason to fear, was filled up with individuals who were his mere creatures. Tiberius indeed restored to the senate part of its former power, but the more the influence of the soldiers increased the more that of the senate declined, which body, as a compensation for this loss, was made a high court of justice, which took cognizance of offences against the state or tho person of the emperor. No provision was made for a regular succession ; the first five emperors all belonged to the Julian and Claudian families. The succession depended upon the will of the actual imperator, who appointed his successor either by adoption or by giving him one of the titles, Caesar and Princeps Juventutis; or by making him his colleague in the quality of tribune or proconsul. In cases where no person was designated the senate exercised the right of election. But this privilege was soon assumed by the soldiers, who proclaimed the emperors, and the sanction of the senate became a mere form. The numerous body-guards of the emperors (praetorians), who in their stronghold (prntorian camp) formed as it were a new Capitol, in effect possessed the sovereign power; and on some occasions they sold the empire to the best bidder. The numerous legions in the provinces too soon became acquainted with this secret of despotism, and availed themselves of it.
The Roman empire, notwithstanding its fast extent at the end of the republic, still continued to increase. Vindolicia, lthntia, Noricum, Pannonia, and Meesia were completely subdued, and made parts of the empire. The Danube was made the boundary in these parts, to secure the empire against the incursions of tho barbarians. The subjugation of Spain was completed by the submission of the warlike Cantabrians. In Germany conquests were also made, but more with a view to secure Gaul than to acquire any new possessions in that country ; and the Rhine may be considered as the frontier on that aide of the empire. In the reign of Trajan the empire attained its greatest extent; Dacia, Assyria, Mesopotamia, Armenia, and Arabia were made Roman pro vince.; but some of these conquests were soon given up, and the Danube and the Euphrates became the boundaries of tho empire. Britain and the southern part of Scotland had been made a province in the reign of Nero. But the internal weakness, resulting from the imperfect union of so many countries and nations, rendered it impos sible to repel the incursions of the barbarians by whom the empire was harassed from about the close of the 4th century. During this period one country was lost after another, and Italy itself was invaded by the Huns under Attila (A.D. 452). In the year A.D. 476 Odoaccr, an officer of the imperial guards and a Goth by birth, dethroned the last emperor Romulus Augustulus, and was saluted by his army King of Rome. The Roman senate implored his protection, and Zeno, the emperor of the East, raised him to the rank of a Roman patricius. Thus ended the Roman empire in the west.