Chakhar was originally one of estates of Khubilai located around Jingzhao (now Xian). The Chakhar people moved from Shaanxi to Southeastern Mongolia in the 15th century. Chakhar became a tümen under Dayan Khan and was led by his successors.
Oppressed by Altan Khan, Chakhar, led by Darayisun, moved eastward onto the Liao River in the middle 16th century. In the early 17th century Lingdan Khan made an expedition to the west because of the Manchu pressure. When he died in Gansu on his way to Tibet, his son surrendered to the Manchu.
The Chakhar royal family kept favorable relations with the Manchu imperial family until Makata Gege, who was a daughter of Hong Taiji and married the Chakhar prince, died in 1663. When the Rebellion of the Three Feudatories erupted in 1673, the Chakhar prince revolted against the Qing Dynasty. He was soon crushed and, as a result, Chakhar was reorganized into the Chakhar Eight Banners and moved to around Zhangjiakou. Chakhar did not belong to a league (chuulghan) but was directly controlled by the Emperor.
Chahar was a province of China.
Chahar is also the name of the Mongolian dialect spoken in the area of Chahar.