Many people liked this new religion. Those who believed in Islam were known as Moslems, and before long, as I have told you, there were as many Moslems or Mohammedans as there were Christians. At first the Moslems tried to persuade others to join simply by talking to them and telling them how fine their religion was, and how much better than what they had already had. But very soon they began to _force_ others to become Moslems whether they wanted to or not. Like the highway robber who says, “Money or your life,” they gave every one a choice. “Money or your life, or be a Moslem!” This may seem a strange way for people to make others believe their religion, but the Moslems said that Allah wanted all people to be Mohammedans, and didn’t want any one who was not. Mohammed only lived for ten years after the Hegira; that is, until 632. But those who came after Mohammed went on with the new religion and kept on conquering and making people Mohammedans with the sword. The new leaders and rulers of the Mohammedans were called caliphs. The second caliph was named Omar. Omar went on to Jerusalem and built a Mohammedan mosque in the place where the temple of Solomon had stood. This mosque which Omar built still stands to-day in the same place in Jerusalem. The Arabs, or Saracens, as they are also called, kept on northward toward Europe and conquered and converted every one to Islam as they went along. Those they could not convert they put to death. At last they reached the City of Constantine, Constantinople, where the people were Christians. This was the gateway from Asia to Europe, and the Arabs tried to get by. But the Christians poured down red-hot tar and burning oil from the walls of the city, and the Moslems had to stop. They could get no farther. Again and again the Moslems tried to capture the city, but without success. Finally, they had to give up trying to get into Europe by this way. Then they tried the opposite direction from Mecca, the long, long, way round to Europe. Across Egypt they went with little difficulty, converting every one to Islam. Further on still they kept going, along the coast of Africa, conquering everything before them until they reached the ocean. Then they turned north, took boats, and crossed over the Strait of Gibraltar and marched on up into Spain. Farther and farther on they went up into France. It seemed as if they would soon conquer all of Europe and make the whole civilized world Mohammedan. But finally, near the town of Tours in France, they met their match. The king of France had a right-hand man named Charles who had been nicknamed Charles the Hammer because he could strike such terrific blows. Charles was called Mayor of the Palace, which merely meant that he was the chief servant of the king, but he was much more able than the king himself. In fact, the king was of very little account.