Sayyed Ala al-Din Hoseyn (Persian: سید علاء الدین حسین) (c.1592 – 5 March 1654), better known as Khalifeh Soltan[a] (خلیفه سلطان), and also known as Soltan al-Ulama (سلطان‌العلماء آملی), was an Iranian statesman and cleric, who served as the grand vizier of the Safavid king (shah) Abbas I (r. 1588–1629), the latter's grandson Safi (r. 1629–1642), and Abbas II (r. 1642–1666).

Later, in 1645, Khalifeh Soltan was re-appointed as grand vizier by the latter's son and successor, Abbas II, whom he became a close companion of, and gained considerable influence.

Khalifeh Soltan's full name was Sayyed Ala al-Din Hoseyn al-Hoseyni Marashi Amoli Isfahani;[1] he was born in ca.

1592/3 in Isfahan, where he grew up; his father Mirza Rafi al-Din Muhammad was a prominent aristocrat who occupied high offices in the Safavid Empire, and belonged to a family known as the "Shahristani sayyids", which was descended from Shah Nimatullah, the founder of the Nimatullahi order.

In late 1624, after celebrating Nowruz, Abbas I left for Georgia to suppress a rebellion, thus leaving the young Khalifeh Soltan in Isfahan, to take care of the Safavid affairs.

On that day, Khalifeh Soltan, who was still new to the grand vizier post, sent 200 soldiers to the convent of the Carmelites, a Catholic religious order.

During his pilgrimage, he had met Ottaqi Efendi, the shaykh of Mecca, who described him as a "man of great scholarship and perspicacity", and someone with whom he had had "many enjoyable sessions of learned discussions".

[4] His established bureaucratic proficiency and past knowledge were definitely the deciding factors in this reappointment, albeit it may be possible that Abbas II recalled him into duty in part with the goal of compressing the discontent about the scarcity of the positions given to men of religion under his predecessor.

[4] The Dutch trader Winninx, who was in Isfahan for transactions with the royal court at that time, commented the following about the situation; "He first refused to accept the post claiming to be too old and not competent enough to carry out the task.

Committing up to his notoriety as a dedicated man and a cleric, he started his second term with an operation countering "sinful behaviour", which targeted betting, prostitution, and wine drinking-activities that were normal in coffee houses and taverns.

The operation was mainly aimed against well-known forms of Sufism, but did not stop Khalifeh Soltan from showing (more virtuous) mystical tendencies, or from becoming one of Abbas II's close companions after the shah started drinking in 1649/50.

[4] A year earlier (1648), Khalifeh Soltan had accompanied Abbas II during his expedition against the Mughals,[7] which ended in a victory for the Safavids, who managed to capture Bost and Qandahar.