Medieval Islamic Empire Bronze Coin - AD 1037–1308 (specify amount)

The Seljuk Empire, or the Great Seljuk Empire, was a high medieval, culturally Turco-Persian, Sunni Muslim empire, established and ruled by the Qïnïq branch of Oghuz Turks.The empire spanned a total area of 3.9 million square kilometres (1.5 million square miles) from Anatolia and the Levant in the west to the Hindu Kush in the east, and from Central Asia in the north to the Persian Gulf in the south, and it spanned the time period 1037–1308, though Seljuk rule beyond the Anatolian peninsula ended in 1194.

The Seljuk Empire was founded in 1037 by Tughril (990–1063) and his brother Chaghri (989–1060), both of whom co-ruled over its territories; there are indications that the Seljuk leadership otherwise functioned as a triumvirate and thus included Musa Yabghu, the uncle of the aforementioned two.

During the formative phase of the empire, the Seljuks first advanced from their original homelands near the Aral Sea into Khorasan and then into the Iranian mainland, where they would become largely based as a Persianate society. They then moved west to conquer Baghdad, filling up the power vacuum that had been caused by struggles between the Arab Abbasid Caliphate and the Iranian Buyid Empire.

The subsequent Seljuk expansion into eastern Anatolia triggered the Byzantine–Seljuk wars, with the Battle of Manzikert in 1071 marking a decisive turning point in the conflict in favour of the Seljuks, undermining the authority of the Byzantine Empire in the remaining parts of Anatolia and gradually enabling the region's Turkification.

The Seljuk Empire united the fractured political landscape in the non-Arab eastern parts of the Muslim world and played a key role in both the First and Second Crusades; it also bore witness to in the creation and expansion of multiple artistic movements during this period. By the 1140s, the Seljuk Empire began to decline in power and influence, and was eventually supplanted in the east by the Khwarazmian Empire in 1194 and the Zengids and Ayyubids in the west. The last surviving Seljuk sultanate to fall was the Sultanate of Rum, which fell in 1308.