Jebel Shomer, an inland division of Arabia, between lat. 25° 40' and 32° N, and Ion. 37° 20' and 47° 20' E., bounded N bythe Syrian desert, N. E. by Irak Arabi, S. E. and S. by the Wahabee sultanate, and W. by Turkish Arabia. It is divided into the provinces of Jebel Shomer, Jowf, Kheybar, Upper Ka-sim, and Teyma, with a total population estimated by Palgrave in 1862 at 440,000, including 106,000 nomadic Bedouins. Jebel Shomer in its general aspect is a flat table land, a large part of which is desert, with occasional oases. These are merely depressions in the desert surface, and take sometimes the form of a long valley covered with a thin soil, under which water may generally be found at the depth of a few feet. Fruits, bushes, herbs, and coarse grass grow in sufficient quantities to supply food for the Bedouins and their camels and flocks. The entire N. portion is covered by a rocky desert. On the E. border, about lat. 31°, is a long valley, called Wady Sirhan or Serhan (valley of the wolf), which extends from near Bozrah in Syria in a S. E. direction to about lat. 29° 20' in Arabia, where its base rests on Wady Jowf, a deep valley lying E. and W., and which may be considered the porch or vestibule of central Arabia. (See Jowf.) The Wady Sirhan is the common route for caravans to and from Syria. S. and E. of Jowf lies a wide expanse of sandy desert.
The caravan route to the province of Jebel Shomer lies across this waste in a S. E. direction through what is called the Nefud or Sand pass, consisting of parallel ridges of loose reddish sand 200 to 300 ft. high, where no water can bo obtained for nearly 100 m. The route runs beside a small range of hills called Jebel Jobbah, a cluster of black granite rocks streaked with red, about 700 ft. high. Beyond them, on the south, is a barren plain, partly white and incrusted with salt, partly green and studded with palm groves, among which is the small village of Jobbah. From the heights overlooking Jobbah are visible in the southeast the main range of Jebel Shomer, and in the southwest the palm groves of Teyma, famed in Arab history, and supposed by some to be identical with the Teman of Scripture. Beyond Jobbah the undulations are not so deep, and the sand has occasional shrubs and tufts of grass. The plain gradually rises as it approaches the mountain ranges, which, stretching N. E. and S. W., cross two thirds of upper Arabia. These ranges, Jebel Adja on the north, the mountains of Upper Kasim on the south, and Jebel Solma between, lie nearly parallel, and are separated by broad plains covered with grass and shrubbery.
Within their limits is the chief centre of population of Shomer. Hayel, the capital, lies in an extensive plain between Adja and Solma, girt on every side by a high mountain rampart. The only approach from the north is by a narrow winding defile through Jebel Adja, which 50 men could defend against thousands. The range of Jebel Adja, or Jebel Shomer as it is now more generally called, is a ragged granitic mass, piled up in fantastic disorder, attaining at times an elevation of 1,400 ft. above the plain, bat Solma does not rise more than 700 or 800 ft. Good crops of grain, fruits, and vegetables are raised by a laborious system of artificial irrigation. The date is the principal fruit. There is a considerable trade by caravans between Hayel and Medina on the southwest, and Riyad, the capital of Ned-jed, on the southeast. Many horses and asses are exported. Upper Kasim, the southernmost province of Shomer, is an elevated plateau, forming part of a long upland belt that crosses diagonally the northern half of the peninsula,, one extremity reaching nearly to Zobeyr, near the head of the Persian gulf, and the other to the neighborhood of Medina. Its surface is covered with shrubs and brushwood, and in spring and summer with grass.
This great plateau is intersected at intervals by long broad valleys, which contain villages built around wells, surrounded by palm groves, gardens, and fields, and varying in population from 500 to 3,000. Dates are exported in large quantities to Yemen and Hedjaz, and cotton is raised to a small extent. - The sultanate of Jebel Shomer originated in the present century. In 1818 Abdallah, an ambitious chief of the family Rashid, was driven out of Hayel by his rival Beyt Ali, who assumed the sovereignty. Abdallah took refuge at the court of the Wahabee monarch, who was then reconstructing his father's dominions, and for his services to him was made absolute governor of Shomer, with right of succession, and supplied with the* means to establish his rule. Beyt Ali and his family were cut off, and Abdallah made himself master of the whole mountain district. He died about 1845, and was succeeded by his son Telal, who extended his dominions, subdued the Bedouins, invited trade from abroad, and established law and order.
Under his rule the country has made rapid advances in civilization and prosperity, and has become virtually independent.