e imamate, which lasted until 1871. For
descriptions of it in the 18th century cf. C. Niebuhr's accounts of
his travels in Arabia in 1761.

_Oman._--Since the separation from the caliphate (before 1000 A.D.) Oman
had remained independent. For more than a century it was governed by
five elected imams, who were chosen from the tribe of al-Azd and
generally lived at Nizwa. After them the Bani Nebhan gained the upper
hand and established a succession of kings (_maliks_) who governed from
1154 to 1406. During this time the country was twice invaded by
Persians. The "kings of Hormuz" claimed authority over the coast land
until the beginning of the 16th century. In 1435 the people rose against
the tyranny of the Bani Nebhan and restored the imamate of the tribe
al-Azd. In 1508 the Portuguese under Albuquerque seized most of the east
coast of Oman. In 1624 a new dynasty arose in the interior, when Nasir
ibn Murshid of the Yariba (Ya'aruba) tribe (originally from Yemen) was
elected imam and established his capital at Rustak. He was able to
subdue the petty princes of the country, and the Portuguese were
compelled to give up several towns and pay tribute for their residence
at Muscat. About 1651 the Portuguese were finally expelled from this
city, and about 1698 from the Omanite settlements on the east coast of
Africa.

For the history of Oman from 661 to 1856 cf. G.P. Badger, _History of
the Imams and Seyyids of Oman by Salil-ibn-Razik_ (London, Hakluyt
Society, 1871). (G. W. T.)

_Wahhabi Movement._--Modern Arabian history begins with that of the
Wahhabi movement in the middle of the 18th century. Its originator,
Mahommed Ibn Abdul Wahhab, was born (1691) at Ayana in Nejd, and after
studying in Basra and Damascus, and making the pilgrimage to Mecca
returned to his native country and settled down at Huremala near
Deraiya. The abuses and corruptions which had overgrown the practice of
orthodox Islam had deeply impressed him, and he set to work to combat
them, and to inculcate on all good Moslems a return to the pure
simplicity of their original faith. In 1742 Mahommed Ibn Saud, sheik of
Deraiya, accepted his doctrines, and enforced them by his sword with
such effect that before his death in 1765 the whole of eastern Nejd and
El Hasa was converted to the faith of Abdul Wahhab, and accepted the
political supremacy of Ibn Saud. His son and successor, Abdul Aziz, in a
rapid series of successful campaigns, extended hi