Ismihan Sultan was the eldest daughter of Ottoman sultan Selim II. She was married to the vizier Sokollu Mehmed Paşa, who reigned as grand vizier for fourteen years under three Ottoman sultans. Along with her husband, she is known as the patron of architectural works that feature prominently in the landscape of Istanbul.
Sources:
Necipoğlu, Gülru. The Age of Sinan: Architectural Culture in the Ottoman Empire, 331-333. London: Reaktion Books, 2005.