The Four Oirats (Written Oirat: ᡑᡈᠷᡋᡈᠨ
ᡆᡕᡅᠷᠠᡑ, Dörbön Oyirad; Mongolian: Дөрвөн Ойрад, romanized: Dörvön Oirad, pronounced [ˈtɵrw̜ʊ̈ɴ ˈɞe̯ɾ(ə)t]; Chinese: 四衛拉特) or Oirat Confederation, formerly known as the Eleuths, was the confederation of the Oirat tribes which marked the rise of the Western Mongols in the history of the Mongolian Plateau.
Despite the universal currency of the term "Four Oirat" among Eastern Mongols, Oirats, and numerous explanations by historians, no consensus has been reached on the identity of the original four tribes. While it is believed that the term Four Oirats refers to the Choros, Torghut, Dorbet and Khoid tribes, there is a theory that the Oirats were not consanguineous units, but political-ethnic units composed of many patrilineages. In the early period, the Kergüd tribe also belonged to the confederation.