Iwan Kisra, which means Iwan of Khusraw, is a monumental iwan or arched reception room that once formed part of a Sasanian palace complex. The iwan and the southern wing of its façade are the only standing remnants of the complex. It is located in Asbanbar, a palace city and one of the several royal foundations around the Sasanians' winter capital of Ctesiphon (Tisfun or al-Mada'in) in lower Iraq on the Tigris. Its date is uncertain, scholars having argued for foundation in both the third century and sixth century, CE.
Today, the arch opens onto a large empty space and is flanked on either side by a monumental facade that once rose 35 meters. The facade, constructed of baked brick, is divided into six horizontal bands of varying height articulated with blind arcades. The arch itself is one of the largest known, the area covered measuring 43.5 meters deep and 25.5 meters wide. It takes the form of a parabola, as was common based on the building techniques at the time, where vaults could be built either with or without centering devices. Here, the vault was constructed without the use of any centering devices, but rather constructed by slanting the walls until they met at a point. This type of construction, where no scaffolding was used to generate a well-rounded shape, produced a parabolic arch.
Flanking the iwan to the north and south were rectangular rooms. A passageway at the rear of the iwan led to a large hall. As the rooms within this complex are extremely large in scale, their use must have been limited to ceremonial functions, with royal residential spaces located elsewhere. Textual sources refer to the great iwan as the place where Khusraw's throne was placed. According to the ninth-century Arab historian al-Tabari, Khusraw's crown had been so heavy that it had to be suspended from the vault of the iwan. A large curtain was also used to separate the space of the iwan from the court in front. Shards of glass mosaic found in the vicinity suggest that mosaics were used for decoration. Arab historian, Qazwini also refers to an illustration of Khusraw mounted on a yellow horse, now lost, on the wall of the throne room, in the entry iwan. The same image is described in a famous ode written by Abbasid poet Walid ibn 'Ubayd al-Buhturi (d. 897/284 AH). Marble was also used on interior surfaces. These decorative elements for the palace were likely imported from Syria.
It is probable that the space onto which the iwan originally opened was a massive courtyard, and that another monumental iwan opening from the opposite end faced it.
The two hypotheses for the complex's foundation date are based on different types of historical sources. Highlighting the style of the blind arcade used in the facade, Oscar Reuther argued for a late antique date, placing it in the first half of the sixth century CE during the reign of Sasanian king of kings Khusraw I Anushirvan (r. 531-579 CE). Ernst Herzfeld, who surveyed the site before Reuther and also had a deep knowledge of medieval textual sources, dated the construction to the reign of Shapur I (r. 239-270 CE). Herzfeld's primary source for this information was the eighth-century translator Ibn al-Muqaffa's edition of the Sasanian chronicle known as the Khudhay-Nama. Although Herzfeld's conclusion remains less popular than Reuther's, the argument at the heart of Reuther's stylistic analysis that the blind arcade on the facade is an idea imported from Byzantine palace architecture is not entirely convincing.1 Although the destruction of the palace is blamed on different individuals by various sources, Abbasid caliph Al-Mansur (r. 754-775) is most commonly mentioned for its ruin.
The Iwan became famous in the Islamic period as a ruin and was described by many poets as both a symbol of the power of the Sasanian Empire and as a reminder of the vicissitudes of time. While it is unclear whether the plan of this and other Sasanian palaces "influenced" the form taken by early Islamic palatine architecture, it is likely that such poetic descriptions inspired the early Muslim rulers, who formulated their own version of monumental, opulent court architecture with a rigorous ceremonial code.2
Reuther, Oscar. "Sasanian Architecture." In A Survey of Persian Art from Prehistoric Times to the Present. Edited by Arthur Upham Pope and Phyllis Ackerman, 515- 517, 543-544. London, New York: Oxford University Press, 1964.
Noldeke, Theodor. 1879. Geschichte der Perser und Araber zur Zeit der Sasaniden: Aus der arabischen Chronik des Tabari, Leyden: Brill.
Spiers, Richard Phené. Architecture east and west; a collection of essays written at various times during the last sixteen years, 75. London: for the committee of the Spiers testimonial by B.T. Batsford, 1905.