The difference that it was to make was not seen just at first. Cæsar went up north to his command. His campaign against the Gauls, of which he himself has written the account in his "Commentaries," are a little out of the direct line of our great story. They had their effect on the big story, for if they had ended in any other way than the way in which they did, if Cæsar had been killed or conquered--and he was nearly killed or conquered more than once--the big story might have gone quite differently. But as it was, {200} in the end--and the end of his campaigns in Gaul did not come until nine years had passed--he was completely victorious. During those years he made an expedition to Great Britain, but did not stay there long. At the end of the nine years he came back. He was chosen as Consul for the second time. He came back to the borders of Italy at the head of his victorious legions. He was commanded by the Senate to disband his troops before coming to Rome to be made Consul. The Senate and Pompey, for Pompey still was chief man in Rome, did not want a general with soldiers devoted to him at the gates of the city. Cæsar halted for a time, while messages about this went to and fro between him and the Senate, the Senate ordering him to disband the troops, and Cæsar refusing. He halted on the banks of a small stream, the Rubicon, which has become very famous because it was the boundary of Italy beyond which he was forbidden to go at the head of troops. Finally, in the year 49 B.C., he determined to go against the order of the Senate and brave the consequences. _Cæsar crossed the Rubicon!_ The crossing of that river meant war. Cæsar knew it. The Senate knew it. Pompey knew it. The great Pompey fled before him, and took command of the Senatorial armies in Greece. Cæsar, who had no fleet, went in pursuit. They met at Pharsalia, in Thessaly, and there was fought one of the great battles of history. Cæsar gained the day, and Pompey again fled, into Egypt. Again Cæsar pursued him, and was met on coming to Egypt by a messenger who thought to find favour with him by bringing him the head of Pompey, who had been murdered. But Cæsar was a generous enemy. {201} Pompey had been his friend, and he mourned his death with respect. [Sidenote: Cleopatra] There was trouble in Egypt at this time. The rulers were supposed to be one of the Ptolemies and Cleopatra, also of the same family, the two sharing the throne. But the Ptolemy had thrust the queen out and claimed to rule alone. Cæsar, captivated by the beauty of Cleopatra, restored her to her share in the government. Then he marched up with his force into Syria. There, too, there was trouble.