chief Companions, to frequent the Caliph’s court. [Sidenote: Death of Abu Bekr’s son.] In this year Abu Bekr lost his son Abdallah, who died from the effects of a wound received at the siege of Tâyif. [Sidenote: Omar Chief Justice.] As supreme judge in civil causes, the Caliph nominated Omar; but warlike operations so occupied men’s minds, that for the time the office was a sinecure. [Sidenote: The first Pilgrimage under the Caliphate. Dzul Hijj. A.H. XI. March, A.D. 633.] The presidency at the annual Pilgrimage is always carefully recorded by the annalists of Islam. The Caliph was too much engrossed with the commotion throughout Arabia to proceed himself to Mecca on the first Pilgrimage of his reign, and he therefore commissioned Attâb, governor of the holy city, to preside in his stead.[95] So ended the first year of the Caliphate. CHAPTER X. CAMPAIGN OF KHALID IN IRAC. A.H. XII. A.D. 633. [Sidenote: Collision with border tribes led to conflict with Roman and Persian empires.] Chaldæa and the south of Syria belong, as well by nature as by population, to Arabia. The tribes inhabiting that region, partly heathen, at the time we write of, but chiefly Christian, formed an integral portion of the Arab race. As these resisted the Moslem columns engaged on the frontier, they were eventually supported by their respective sovereigns--the western tribes by the Byzantine empire, and the eastern by Persia. Thus through them the struggle spread, and soon brought Islam face to face in mortal conflict with the two great Powers of the east and west. [Sidenote: History of Byzantine and Persian campaigns dependent exclusively on Arabian sources.] The sources of our history, being purely Arabian, throw little light on the condition of the provinces to which the scene will now be transferred. With the Roman empire, the Arabs of the peninsula had never at any time much acquaintance or concern, and the Byzantine annals of Syria are suddenly quenched by the Saracenic cataclysm. A few brief lines is all we have from them of the momentous events on which we are about to enter. Of the Eastern empire, succeeding as the Arabs did to the Sassanide dynasty, they naturally had a greater interest in the antecedents; and we have, through their historians, glimpses of the anarchy that now prevailed in Persia. But even this is, at the best, fragmentary and imperfect.