In 1630 the Turks withdrew from the Yemen, and the government fell into the hands of a descendant of Ali ibn Abou Taleb, who married Fatima, the daughter of the Prophet Mahammed. This man was by name Kasim, whose full titles were Mansur el-Kasim el-Kebir. His ancestor, El-Hadi Yahia, had founded the Rassite dynasty in 284 A.H. The family of Kasim, which now commenced to hold the government of the Yemen, continued until the conquest of Sanaa by the Turks in 1872 to fill the posts of Imams.[19] A few words are necessary in explanation of this title, by which the rulers of the Yemen have been so long known. The word Imam literally means the leader of prayer in the mosque. Thus it will be seen that the office was not merely a temporal one, but was also imbued with religious rights, enjoyed on account of their descent from the Prophet. Not daring to assume the title of “Caliph,” they preferred the minor one “Imam,” though practically by carrying out the old-established customs, such as changing their names on succeeding to power, they took upon themselves the position enjoyed by the direct successors of Mahammed himself. The office was a hereditary one, and generally succeeded to by primogeniture, provided the eldest son was of an age and character suitable to his being able to carry out the necessary duties. Niebuhr gives an interesting account of the principal officers in the service of the Imams, a portion of which may be mentioned here.[20] The various provinces were, he says, under the governorship of a “Dowla,” or military governor, who was responsible for his district, collected the taxes, commanded the troops, and regulated all local affairs. It was customary for a man only to hold the office for a few years, in order to prevent his acquiring great wealth or influence. Their position was always an uncertain one, as they necessarily made many enemies, who were ready to do them some ill turn at headquarters. The Bas-Katéb was secretary, appointed by the Imam, under each, whose principal work was to spy upon and report to their lord and ruler the actions of the “Dowla.” As ordained by the tenets of Islam, all cases relating to laws laid down in the Koran were tried by the Cadi, or chief judge. The ports were under the rule of three officers,—an Amir el-Bahr, or captain of the port; an Amir es-Sôk, whose duty lay in regulating the markets; and a Sheikh el-Beled, who collected the taxes. El-Kasim was succeeded by his son El-Muayyad Mahammed, who in turn was succeeded by his brother Ismail, who lived a life of supreme simplicity, and died after a long reign, mourned by the whole country. So Imam succeeded Imam with all the changing fortunes of oriental rulers, and without apparently performing any deeds which redound to their own praise or raised the splendour of their country. In all probability their lives were simply spent in Eastern uxoriousness, and in keeping in order the turbulent tribes by which they were surrounded.