Bagirmi's precolonial history centered around the affairs of its ruler (the mbang ) and his court. There were four periods: formative, offensive, counteroffensive, and final.
The formative period (c. 1522-1608) roughly corresponds to the rule of the first four sovereigns. Tradition suggests that Dala Birni, the first of these, led followers from Kenga territory around 1522. This band was believed to have stopped under a tamarind tree (Tar Barma: mas ), where there was a young Fulani milkmaid named Enya. Later, a settlement was built around this tree, which, to commemorate both the tree and the milkmaid, became known as "Massenya," and it became Bagirmi's capital. Dala Birni is supposed to have protected the people in this area, and in return they paid tribute, the amount of which became the name of the kingdom (see "Identification"). Nothing is known about the second and third sovereigns. The fourth sovereign is remembered for imposing Islam upon Bagirmi, greatly expanding the state, and creating much of its governmental structure. With his death, traditionally set at about 1608, Bagirmi entered a more offensive phase.
During the period from about 1608 to 1806, Bagirmi may well have enjoyed a rough hegemony in east-central Sudan. According to its traditions, this pugnacious polity created tributaries to the north among the Medogo, the Bulala, the Kuka, and the Babelyia; to the west among the Kotoko; to the south among the Sarua, the Somrai, the Niellim, the N'Dam, and the Bua; and to the east among the Kenga and the Sokoro. The town of Bidiri was a center of Islamic learning, and its merchants were active throughout the region. This period ended at the close of the eighteenth century, when Wadai attacked. Wadaian aggression resulted from the conviction that Gaurang, Bagirmi's ruler, had committed incest by marrying a sister. Gaurang's defeat, in about 1806, initiated a period lasting until the arrival of the French, during which Bagirmi, seeking to regain its lost preeminence, mounted counterofifensives against both Wadai and Bornu. These actions were generally unsuccessful; however, there was expansion to the south.
At the end of the nineteenth century, France had decided to incorporate the central Sudan into its empire. The interval (1897-1912) prior to formal French colonization constituted the final period. Bagirmi signed a treaty with France in 1897, hoping thereby to gain support in conflicts with Wadai. Officials of Bagirmi also went behind the backs of the French and conspired with Wadai. After a final struggle with the French that ended in 1912, Bagirmi became a circonscription under the direct administration of a French chef de circonscription. Thus, during the subsequent colonial period (1912-1960) and, after 1960, as part of Chad, Bagirmi was no longer independent.