Eyalet of Rûm (Ottoman Turkish: ایالت روم; Eyālet-i Rūm; originally Arabic for Rome), later named as the Eyalet of Sivas (Ottoman Turkish: ایالت سیواس; Eyālet-i Sīvās), was an Ottoman eyalet in northern Anatolia, founded following Bayezid I's conquest of the area in the 1390s. The capital was the city of Amasya, which was then moved to Tokat and later to Sivas. Its reported area in the 19th century was 28,912 square miles (74,880 km2).
Rûm was the old Seljuk Turkish designation for Anatolia, referring to the Eastern Roman Empire and in European texts as late as the 19th-century the word Rûm (or Roum) was used to denote the whole of central Anatolia, not just the smaller area comprising the Ottoman province (see Sultanate of Rum).
When the Ilkhanid ruler Ebu Said died in 1335, administration of Asia Minor was entrusted to his former governor Eretna Bey, an Uyghur Turk. Eretna Bey ultimately declared independence, seeking the protection of the Mamluks, who were rivals of the Ilkhanids. He captured the area around Sivas-Kayseri, eventually establishing an emirate of Eretna, which grew stronger during the rule of his son, Mehmed Bey.
In 1381 Kadı Burhaneddin a kadı in Kayseri who was also appointed vizier to represent the emirate of Eretna in that town, replaced the Eretnid as ruler of Sivas and also captured Amasya and Tokat. His principality managed to resist interference in central Anatolia from both the Akkoyunlus and the Ottomans until it collapsed with his death in 1398.
Organisation of the eyalet in the 17th century, from the accounts of Evliya Çelebi: "The Defter (treasury) has a Kehiya and Emin, the Chavushes have the same; there is besides a captain and Defterdar of the feuds".
Administrative divisions 
The eyalet of Sivas consisted of seven sanjaks between 1700 and 1740:
- Sanjak of Sivas (Paşa Sancağı , Sivas)
- Sanjak of Amasya (Amasya)
- Sanjak of Janik (Canik Sancağı, Samsun)
- Sanjak of Diwriji (Divriği Sancağı, Divriği)
- Sanjak of Arabgir (Arabgir Sancağı, Arapgir)
- Sanjak of Chorum (Çorum Sancağı, Çorum)
- Sanjak of Bozok (Bozok Sancağı, Yozgat)
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