A league (Mongolian: Ayimagh.svg (ᠠᠶᠢᠮᠠᠭ) ayimaγ [æːmɑ̆ɡ̊] Aimag; historically, Cighulghan.svg čiγulγan [t͡ʃʰʊːlɡ̊ɑ̆n] Qûûlgan; Chinese: 盟; pinyin: méng) is an administrative unit of the Inner Mongolia Autonomous Region, People's Republic of China.
Leagues are the prefectures of Inner Mongolia. The name comes from a kind of ancient Mongolian administrative unit used during the Qing Dynasty in Mongolia. Mongolian Banners (county level regions) were organized into conventional assemblies at the league level. During the ROC era, the leagues had a status equivalent to provinces. Leagues contain banners, equivalent to counties.
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