Joktan or Kahtan was the first king of Yemen. His successors reigned 2,000 years in that country. Saba, the fourth after him, built the capital and called it alter his name; hence the Sabaeans. He converted one of the valleys in his territory into a large lake, five leagues in length, by constructing a mole or bank across its lower extremity. The water was thence conducted to the fields, gardens, and houses of the inhabitants, and the lands thus irrigated became very productive. Bilkis, one of the queens of Yemen, according to the Arabs, was the famous queen of Sheba who visited Solomon. From her designation queen of the south, and the description of her presents to Solomon, gold and spices, there is little doubt that Arabia, and Yemen in particular, was the native country of this princess. The French traveller T. J. Arnaud, who visited this region in 1843, found among the ruins abundant evidence of its former greatness in the massive blocks of stone covered with inscriptions in the Himyaritic character, and in the ruins of buildings and temples which must have once approached in magnificence those of Palmyra or Tadmor. Himyar, the immediate successor of Saba, is supposed to have been the founder of the city of Mareb, and to have invented the Himyaritie characters.

After an inundation caused by the bursting of the immense reservoir built by Saba the tribes of this kingdom were scattered, and were not again united till a century later under Tobba I., about A. D. 175. Under him and his successors Yemen rose to more than its ancient splendor. Assad Abu-karb (220) invaded and subdued Tehama, defeated the Tartars in Azerbijan, plundered many cities of Khiva, and seems to have carried his arms into Bokhara. Tobba II. in 297 invaded Hedjaz and besieged Yathreb (now Medina), a city inhabited by Jewish refugees after the destruction of Jerusalem. While there he was converted to Judaism, and on his return home all the nation embraced the Mosaic faith. Dunawas in 480 was a furious persecutor of the Christians, and is said to have burned 20,000 of them in a pit tilled with combustibles. The Christian king of Abyssinia sent an army under the command of his son Arayat, with orders to slay every Jew and plunder the country. Dunawas was routed, and cast himself into the sea, and the race of the Himyarite princes became extinct.

Arayat was confirmed in the government of Yemen, and the Abyssinians ruled it for 72 years, until Seif, a descendant of the Him-yarites, obtained from Chosroes, king of Persia, an army with which he wrested the power from the hands of the Abyssinians. He was appointed viceroy of the king of Persia, to whom he paid an annual tribute. After Seifs assassination by an Abyssinian slave, Yemen was governed by Persian satraps under the title of emirs till it was subdued by the lieutenants of Mohammed. - The kingdom of Hira in Irak was founded by some of the dispersed clans after the inundation in Yemen. Numan I., about A. D. 400, signalized himself by his conquests in Syria, building numerous vessels on the Euphrates, and adorning the capital with palaces, gardens, and hunting parks. Numan is said to have become a convert to Christianity and abdicated the throne to live in retirement. Mundar II., who reigned about 493, proved a valuable ally to the Persian monarch Kobad in his successful invasion of the Roman territories.

In the reign of Mundar V. (633) the kingdom of Hira was invaded and subdued by the lieutenants of Mohammed. Other colonies of Arabs migrated northward into the territory of Damascus, where they founded a dynasty of kings called-the Gassa-nites. Several small principalities existed in those districts before their arrival, the chief of which was the tribe of Silh, who had become converted to Christianity, in consequence of which the Roman emperor invested them with the government of the Syrian Arabs. These the emigrants (the tribes of Aus and Khasraj) expelled, slew many of their petty princes, and established their own sovereignty over these conquered territories, which lasted for about 400 years, when it was extinguished by Moslem conquests. - The Nabathaean Arabs, or Ishmaelites, long preserved a distinct name as a nation, asserting their independence alike against the armies of Egypt and Ethiopia, of the Jews, Assyrians, Greeks, and Romans. "It was extremely difficult," says Diodorus Siculus, "either to attack or subdue them, because they retired to their deserts; and if an enemy ventured to follow them, he was sure to perish of thirst and fatigue, for the wells were only known to themselves." In the time of the Assyrian and Babylonian empires these wild tribes remained either wholly independent, or acknowledged a temporary alliance with their monarchs.

The Medes and Persians under Cyrus and Cambyses found it necessary to have a friendly understanding with the Nabathaeans to secure a safe passage into Egypt. In 312 B. C. Antigonus, one of the successors of Alexander the Great, made an unsuccessful incursion into the territory of the Nabathaeans, and in 310 Demetrius, his son, invaded them again. One of the Ptolemies annexed a narrow strip of Arabia to his dominions. In 219 Antiochus the Great captured the city of Rabbath Moab and subdued several tribes. After that the northern Arabs were frequently involved in wars with the new Jewish state, and fortified several cities on its border, as Bostra, Medabah, and Hesbon. Several Roman proconsuls of Syria undertook expeditions against them, but without any further advantage than the payment of a tribute or temporary cessation of hostilities. - In the reign of Augustus, Aelius Gallus, prefect of Egypt, undertook his famous expedition into Yemen at the head of 10,000 Roman legionaries, 500 Jews, and 1,000 Nabathaeans; 80 ships of war and 130 transports conveyed these troops down the Red sea under the guidance of Syllias, by whose treachery numbers of the vessels were wrecked. Gallus penetrated as far as Mariaba, represented as the capital of the Rahminites, but effected nothing.

Other useless expeditions followed. In A. D. 362 the army of the emperor Julian besieged and destroyed Anbar, the capital of the kings of Hoja. - A new era dawned on Arabia at the birth of Mohammed (about 570). His doctrines soon gained a firm foothold, and Mecca once conquered, he found nearly the whole peninsula at his feet. Abu-Bekr, Omar, Othman, and Ali, who succeeded Mohammed in turn under the title of caliph or emir-el-mumenin, " commander of the faithful," carried forward what he had begun. In the reign of Ali, Moawi-yah, governor of Syria, cast off his allegiance, was proclaimed caliph by the western provinces, penetrated into Hedjaz, reduced Medina and Mecca, and extended his conquests as far as Yemen. A few months after Ali's death the sovereignty passed into the hands of Moawiyah, the first prince of the dynasty of the Ommiyades, who held the supreme power over the Moslem empire till A. D. 750. This period is marked by internal dissensions and bloody struggles. Walid I., one of this line, abolished the use of the Greek language and characters, which had hitherto been employed in keeping the accounts, and ordered his clerks and secretaries to substitute the Arabic, a change to which very probably we owe the invention or at least the familiar use of our present numerical fig-ures. To this dynasty, which ruled for nearly 90 years, succeeded that of the Abbassides, who transferred the seat of the caliphate from Cufah to Bagdad, and held sway over a large part of the Mohammedan countries from the 8th to the 13th century.

The subsequent history of Arabia is but a succession of quarrels among its numerous petty chiefs, except the reform movement of the Wahabees, a sect founded in the middle of the 18th century by Mohammed ibn Abd-el-Wahab. (See Wahabees.) In 1870 and 1871 a rebellion broke out among the Bedouins in Hedjaz, which was with difficulty suppressed by the Turkish troops. - See "History of Arabia," by A. Crichton (Edinburgh, 1834), and "Journey through Central and Eastern Arabia," by W. G. Palgrave (London, 1871).