At Xeres they were met by Roderick, the "last of the Goths," who was killed, and whose army was put to flight by the forces of the Saracens, or Moors as they were called after their settlement in Mauretania or Morocco, just across the straits. But the conquest of Spain by the Moors, teeming as it is with romantic interest, is too long to be related here, and we must retrace our steps to the East. By the end of the first half of the eighth century, and only a little over a hundred years after Mohammed's death, the Saracens had brought their career of conquest almost to an end, and were firmly established as "the most potent and absolute monarchs of the globe." One determined attempt, indeed, was made during the latter half of the century to take Constantinople, the capital of the Eastern Empire. A battle was fought beneath the {40} walls of the city, and the Saracens were victorious; but they were prevailed upon to retire on the promise of an immense yearly tribute. The beginning of the ninth century saw the Eastern and Western worlds ruled respectively by those two famous monarchs of history and romance, Haroun-Al-Raschid and Charlemagne. The first is familiar to most of us through the enchanting pages of the _Arabian Nights_, but history unfortunately gives us a darker portrait of the renowned Caliph, painting him as a jealous and selfish tyrant. He was, however, a patron of literature and of art, which distinguishes him from his predecessors, who were merely warriors. He could fight, too, on occasion, both with tongue and sword. A new Emperor of Constantinople chose to refuse the tribute promised by the late Empress in these words. "Nicephorus, King of the Greeks, to Haroun, King of the Arabs. "The late Queen was too humble; she submitted to pay tribute to you, though she should have exacted twice as much from you. A man speaks to you now; therefore send back the tribute you have received, otherwise the sword shall be umpire between me and thee." The Caliph replied in unmistakable terms-- "In the name of Allah, most merciful!" "Haroun-al-Raschid, Commander of the Faithful, to Nicephorus, the Roman dog. "I have read thy letter, O thou son of an unbelieving mother! Thou shalt not hear, but thou shalt see my reply." [Illustration: _Pilgrims of the XIth Century journeying to the Holy City_] Forthwith a huge force crossed over into the domains {43} of Nicephorus, and only the promise to pay the tribute twice, instead of once a year, induced the Caliph to withdraw his forces.