The Eretnids (Turkish: Eretna Beyliği) were a dynasty that ruled a state spanning central and eastern Anatolia from 1335 to 1381. The dynasty's founder, Eretna, was an Ilkhanid officer of Uyghur origin, under Timurtash, who was appointed as the governor of Anatolia. Some time after the latter's downfall, Eretna became the governor under the suzerainty of the Jalayirid ruler Hasan Buzurg. After an unexpected victory at the Battle of Karanbük, against Mongol warlords competing to restore the Ilkhanate, Eretna claimed independence declaring himself the sultan of his domains. His reign was largely prosperous earning him the nickname Köse Peygamber (lit. 'the beardless prophet').

Eretna's son Ghiyath al-Din Muhammad I, although initially preferred over his older brother Jafar, struggled to maintain his authority over the state and was quickly deposed by Jafar. Shortly after, he managed to restore his throne, although he could not prevent some portion of his territories from getting annexed by local Turkoman lords, the Dulkadirids to the south, and the Ottomans to the west. In 1365, when he had recently put an end to the revolt of his vizier (chief minister), he was murdered by his emirs (vassals) in Kayseri, the capital.

His 13-year-old son, Ala al-Din Ali, was largely not allowed to interfere in administrative matters by the local emirs, who had been enjoying a substantial degree of autonomy since Eretna's demise. Ali lacked necessary skills of governance and was described to have only cared for personal pleasures. The state's borders continued to shrink, and the capital temporarily came under Karamanid control. Kadi Burhan al-Din rose to power as the new vizier and further dispatched Ali to command several largely unsuccessful campaigns. Ali died of the plague in August 1380 amidst one of those expeditions. The fourth Eretnid sultan, Muhammad II Chelebi was 7 years old when his father died. His regent Burhan al-Din toppled him in less than a year and proclaimed himself as the new sultan by January 1381, ending the Eretnid dynasty's political presence.

There is a scant number of surviving buildings and literary works identified with the rule of the Eretnids. This contrasts with the neighboring contemporary states, who left a greater architectural legacy.

The Ilkhanate emerged in West Asia under Hulagu Khan (r. 1256–65) as part of the division of the Mongol Empire that started with Möngke Khan's reign (r. 1251–59). After half a century, the death of the seventh Ilkhan, Ghazan (r. 1295–1304), marked the height of the state, and while his brother Öljaitü was capable of maintaining the empire, his conversion to Shiism sped up the impending fall and civil war in the region.

Of Uyghur stock, Eretna was born to Jafar or Taiju Bakhshi, a trusted follower of the second Ilkhanid ruler Abaqa Khan (r. 1265–82), and his wife Tükälti. His name Eretna is popularly explained to have originated from the Sanskrit word ratna (रत्न) meaning 'jewel'. This name was common among the Uyghurs following the spread of Buddhism, and Eretna may have come from Buddhist parentage.

Eretna migrated to Anatolia following his brothers' execution due to a rebellion they joined and his Chobanid master Timurtash's appointment as the Ilkhanid governor of the region by Ilkhan Abu Sa'id and his father, Chupan. Eretna's master Timurtash eventually rebelled against the Ilkhanate in 1323, during which time Eretna went into hiding. However, the Ilkhan's weak authority and influence over the state of Timurtash's father, Chupan, led to the pardoning of Timurtash and the restoration of his position as the governor of Anatolia. He later led an extensive series of campaigns against the Turkoman emirates in Anatolia. Upon the news of his brother Demasq Kaja's death on 24 August 1327, Timurtash retreated to Kayseri, and following his father's death, he fled to Mamluk Egypt in December while also planning to come into terms with Abu Sa'id. He was later killed on the orders of the Mamluk sultan. Fearing punishment during Timurtash's absence, Eretna took refuge in the court of Badr al-Din Beg of Karaman. Timurtash was replaced by Emir Muhammad from the Oirat tribe, who was the uncle of Abu Sa'id.

Eretna was later involved in a plot against the Ilkhan in 1334 but received a pardon and returned to Anatolia from the Ilkhanid court in Iran. With Abu Sa'id's death in 1335, the Ilkhanid period practically came to an end, leaving in its place continuous wars between several warlords from princely houses, namely the Chobanids and Jalayirids. Back west, Eretna came under the suzerainty of the Jalayirid viceroy of Anatolia, Hasan Buzurg, but had already established his supremacy in the region to a considerable degree. Hasan Buzurg left Eretna as his deputy in Anatolia when he departed east to oppose the Oirat chieftain Ali Padishah's attempt to occupy the Ilkhanid throne. Eretna was officially appointed as the governor of Anatolia by Hasan Buzurg following his victory against Ali Padishah. However, shortly after, Hasan Kuchak gained power in the Ilkhanid domains in the east in 1338. Hasan Kuchak was the son of Timurtash and had effectively become the pretender of his father's legacy. He defeated the Jalayirids near Aladağ and pillaged Erzincan.