Sayyida Shirin

Sayyida Shirin (), also simply known as Sayyida, was a Bavandid princess, who was the wife of Buyid ruler of Ray, Fakhr al-Dawla. She was the "de facto" ruler of Ray during the reign of her son, Majd al-Dawla (r. 997–1029).
Origins.
According to the medieval historian Hilal al-Sabi' and the modern historian Madelung, Sayyida Shirin was the sister of the Bavandid ruler al-Marzuban. However, according to the Qabus-nama made by the Ziyarid ruler Keikavus (who was a neighbor of the Bavandids and of Bavandid descent himself), Sayyida Shirin was the niece of al-Marzuban. Hugh N. Kennedy calls her the daughter of a certain Bavandid ruler ("ispahbadh") of Tabaristan named Sharwin, who may be the Bavandid ruler Sharwin III, who was the brother of al-Marzuban. Sayyida Shirin also had a brother named Rustam Dushmanziyar, whose son Muhammad ibn Rustam Dushmanziyar became the founder of the Kakuyid dynasty. 
Although Sayyida is called a Kurd in some sources, she is generally agreed to be from the Bavand dynasty, which was then of Daylamite origin. Encyclopædia Iranica also states that; “it should be remembered that “Kurd” in the sources of the 10th-11th centuries refers to all the transhumants of the Zagros region including the Lors.”
Biography.
At an unknown date, Sayyida Shirin married Fakhr al-Dawla, and bore him two sons named Abu Taleb Rostam and Abu Taher in the 990s. Fakhr al-Dawla later died in 997 and was in Ray succeeded by Abu Taleb Rostam, who was given the "laqab" of "Majd al-Dawla". Meanwhile, Abu Taher was given the "laqab" of "Shams al-Dawla", and became the ruler of Hamadan. Since both brothers were in the age of minority, power was assumed by Sayyida. Both sons initially declared themselves independent and assumed the title of Shâhanshâh, but by 1009 or 1010 at the latest had recognized the authority of their relative Baha' al-Dawla, who controlled Fars and Iraq, and abandoned the title.
In 1006 or 1007, with the assistance of his "vizier" Abu 'Ali ibn 'Ali, Majd al-Dawla attempted to throw off the regency of Sayyida. Sayyida, however, escaped to the Kurd Abu Najr Badr ibn Hasanuya, and together with Shams al-Dawla they put Ray under siege. After several battles, the city was taken and Majd al-Dawla was captured. He was imprisoned by Sayyida in the fort of Tabarak, while Shams al-Dawla took to power in Ray. After a year, Majd al-Dawla was released and reinstated in Ray; Shams al-Dawla returned to Hamadan. Power continued to be held by his mother. However, Shams al-Dawla later tried to seize Ray from Majd al-Dawla, but was stopped by Sayyida. Sayyida later died in 1028.