The Haseki Hürrem Sultan Mosque in Istanbul’s Fatih district stands out as the main structure of the Haseki Complex, considered among the early examples of classical Ottoman architecture and the first work designed by chief imperial architect Mimar Sinan.
The mosque was commissioned in the 16th century in the name of Hürrem Sultan, the wife of Sultan Suleiman the Magnificent.
Originally built between 1538 and 1539 with a single-domed plan, the mosque was expanded in 1612 by the era’s chief architect, Sedefkar Mehmed Ağa. The renovation added a second domed section to the building, giving it its present appearance.
The structure was planned not only as a place of worship but also as the center of a large külliye complex. The complex included a madrasa, a darüşşifa (hospital), an imaret (soup kitchen), a sıbyan mektebi (primary school) and a bathhouse.
Holding an important place in Ottoman social life, the complex played a significant role among Istanbul’s charitable institutions, particularly through its hospital and soup kitchen.
Architecturally, the mosque is regarded as one of the early examples of classical Ottoman mosque design. Built of cut stone, its interior features a simple and balanced architectural arrangement.
Today, with its architectural features and historical identity, the Haseki Hürrem Sultan Mosque is considered among Istanbul’s significant cultural landmarks and an important example of the Ottoman külliye tradition that incorporated social welfare institutions.
Resul Yelen, a faculty member at the Department of Turkish and Islamic Art at Istanbul Medeniyet University’s Faculty of Letters, told state-run Anadolu Agency that construction of the Haseki Sultan Complex began in 1538 with the building of the mosque.
Yelen noted that the structure was commissioned by Sultan Suleiman the Magnificent for his wife Haseki Hürrem Sultan as part of the külliye complex, adding that Haseki Street effectively divides the complex into two sections.
“This is the first work of Mimar Sinan after he became chief imperial architect,” Yelen said. “To its north stands the mosque, while to the south are the soup kitchen, primary school, hospital and a fountain. According to inscriptions on the mosque, construction began in 1538 and was completed within a year. The other structures were finished about 12 years later,” he added.
Yelen explained that the mosque was originally built with a square plan and a single dome.
“In 1612, according to an inscription referring to the ‘increase of the congregation,’ the structure was expanded. During the reign of Sultan Ahmed, Sedefkar Mehmed Ağa — who was also a student of Mimar Sinan — extended the mosque eastward, effectively enlarging the work of his master,” he said.
With the expansion, the mosque’s eastern wall was removed and a new square-plan, single-domed space supported by two columns was added to the east. During the renovation, the mihrab was moved to the center of the structure in order to maintain symmetry.
Yelen said the interior space of the mosque is divided into two domed sections by two columns.
“The transitions to the domes use what we call oyster-shell squinches. The walls combine stone and brick used as tie beams. In the portico area, five bays were created with columns featuring diamond-shaped capitals,” he said.
Although many decorative painted ornaments can be found inside the mosque, most have been renewed over time. Some retain their original characteristics, while others have been restored to resemble the original style.
The mihrab, which was repositioned to the center, features dense painted ornamentation. Floral motifs emerging from vases and relief decorations appear on the borders, while a lamp motif is placed in the middle of the niche — likely added during the Ottoman westernization period.
Yelen also noted that the area where the complex stands had been known as Haseki since the 19th century.
“When the complex and mosque were first built, the area was actually known as Avrat Pazarı, meaning Women’s Market,” he said, adding that the traveler Evliya Çelebi mentioned that Sultan Suleiman had commissioned the structure there as a gesture for Hürrem Sultan.
Yelen also highlighted the richly decorated stone portal of the mosque, which features oyster-shell and muqarnas motifs, repeated both in the portal and in the dome transitions.
Two additional inscriptions are located beside the portal. The inscription on the right contains the Kelime-i Tevhid, while the one on the left repeats the name of the Prophet Muhammad four times, written in the makili calligraphic style.
Yelen added that Hürrem Sultan commissioned charitable structures not only in Istanbul and Anatolia but also in Jerusalem, noting that a soup kitchen established there continues to operate today.
