There are many historical reasons for the emergence of the League Flag. During the period of Jurchen clan commune, there was a hunting organization called Lu Niu. That is, each time 10 is taken as the unit, each arrow is taken and one person is chosen as the leader. After Nurhachi established the slavery regime, Lu Niu was expanded to 300 people, and then a larger administrative unit, Gushan, was established on it, first four, and then eight, which were marked with yellow, red, blue, white, yellow, red, blue and white flags respectively, so Gushan was translated as "Gushan" in Chinese. Later, the Qing dynasty also compiled the Mongols into the Eight Banners, that is, the Eight Banners of Mongolia.

In order to consolidate its rule in Mongolia, the Qing government also stipulated that several neighboring flags held a group meeting every three years, and the address of the group meeting was designated by the Qing government. Once this place was designated, it became the name of the alliance. During the alliance, there was a leader and several deputy leaders. The leader of the League is only the convener of the League and does not interfere in the internal affairs of each flag.

The Qing government once divided Inner Mongolia into 49 banners and 6 leagues. This flag and alliance continue to be an administrative division. After the establishment of Inner Mongolia Autonomous Region, it still retains the title of League Flag. The Union is equivalent to the region, the flag is equivalent to the county, Sumu is equivalent to the township, and Gacha is equivalent to the village.