Background
Yahya Sharaf ad-Din bin Shams ad-Din bin Ahmad was a grandson of the imam al-Mahdi Ahmad bin Yahya (d 1436) and was born in north-western Yemen.
Yahya Sharaf ad-Din bin Shams ad-Din bin Ahmad was a grandson of the imam al-Mahdi Ahmad bin Yahya (d 1436) and was born in north-western Yemen.
His period as imam covered the period from 1506 to 1555, though his political power ended in about 1547. At this time there was another imam in the Yemeni highlands, an-Nasir al-Hasan, who was however more a man of letters than a politician. However, the Tahirides were defeated by the Mamluks from Egypt in 1517 and the sultan Amir was killed.
Shortly afterwards, the Mamluk sultanate in Egypt was in turn defeated by the Ottoman sultan Selim I. The Mamluk troops in Yemen, as a consequence, had to acknowledge the overlordship of Selim. The weak garrison in San'a had to withdraw, and the important city was taken over by al-Mutawakkil Yahya Sharaf ad-Din. Ta'izz was taken in 1534, followed by Khanfar, Lahij and Abyan.
However, the Ottoman Turks had a vital interest in securing Yemen, which was described as being "more flourishing than the province of Egypt". At this time the Portuguese seafarers had become a nuisance in the Indian Ocean region, threatening to cut off trade between the Red Sea and the Indian coast. There were therefore good strategical reasons to control south-western Arabia.
An Ottoman expedition established a small enclave in Zabid in 1539, but their little enclave was contained by the imam's forces for eight years. However, dissension within the imam's immediate family played into the Turks' hands. The Turkish advance could not be stopped, however.
Udzimir Pasha took San'a through treachery in the same year and 1,200 inhabitants were massacred. Al-Mutahhar continued the anti-Ottoman struggle in the highlands. The old imam died in 1555 in Zafir.