The Mongol invasions of the Islamic world began in 1221 with the conquest of eastern Iran. A more devastating wave of conquest, however, came with Genghis Khan’s grandson Hülegü, when Mongol forces subjugated all of Iran and by 1258 had also taken Baghdad, thus bringing to an end the Abbasid caliphate (750–1258). Establishing rule over most of West Asia, including Iraq, Iran, Khurasan, the Caucasus, and parts of Asia Minor, Hülegü (r. 1256–65) assumed the title of “Il-Khan,” meaning lesser Khan, subordinate to the Great Khan ruling in China. This branch of the Mongol dynasty, which became known as the Ilkhanids (1256–1353), centered its power in northwest Iran.
Although Mongol conquests initially brought devastation and affected the balance of artistic production, in a short period of time, the control of most of Asia by the Mongols—the so-called Pax Mongolica—created an environment of tremendous cultural exchange. Following the conversion to Islam of Il-Khan Mahmud Ghazan (r. 1295–1304) in 1295 and the establishment of his active cultural policy in support of his new religion, Islamic art flourished once again. East Asian elements absorbed into the existing Perso-Islamic repertoire created a new artistic vocabulary, one that was emulated from Anatolia to India, profoundly affecting artistic production.
During the Ilkhanid period, the decorative arts—textiles, pottery, metalwork, jewelry, and manuscript illumination and illustration—further developed along established lines. The arts of the book, however, including illuminated and illustrated manuscripts of religious and secular texts, became a major focus of artistic production. Baghdad became an important center once again. In illustration, new ideas and motifs were introduced into the repertoire of the Muslim artist, including an altered and more Chinese depiction of pictorial space, as well as motifs such as lotuses and peonies, cloud bands, and dragons and phoenixes. Popular subjects, also sponsored by the court, included well-known stories such as the Shahnama (Book of Kings), the famous Persian epic. Furthermore, the widespread use of paper and textiles also enabled new designs to be readily transferred from one medium to another.
Along with their renown in the arts, the Ilkhanids were also great builders. The lavishly decorated Ilkhanid summer palace at Takht-i Sulaiman (ca. 1275), a site with pre-Islamic Iranian resonances, is an important example of secular architecture. The outstanding Tomb of Uljaitu (built 1307–13; r. 1304–17) in Sultaniyya, however, is the architectural masterpiece of the period. Following their conversion to Islam, the Ilkhanids built numerous mosques and Sufi shrines in cities across Iran such as Ardabil, Isfahan, Natanz, Tabriz, Varamin, and Yazd (ca. 1300–1350). After the death of the last Ilkhanid ruler of the united dynasty in 1335, the empire disintegrated and a number of local dynasties came to power in Iraq and Iran, each emulating the style set by the Ilkhanids.