This is one of the oldest Sotho-Tswana tribes. The tribe broke away from the Baurutshi in an area now called South Sudan and continued living side by side with the Baurutshi and later the Bakoena in an area called the Great Lakes region, where they also traded with other Bantu-Swahili groups. Some historical theorists say that Barolong gave birth to Basotho, supported by the fact that they speak a more Sotho-related dialect and traveled south the same way the Sothos claim to have traveled. The majority of Basotho are of Rolong origin in Lesotho and the Orange Free State.
The Barolong people are reported to be descendants of King Morolong, who ruled in 1240 (this interestingly was around the time when the Hurutshe-Kwena cluster had already crossed the Zambezi). He adopted Tholo (kudu) as the Barolong totem. The most famous of the Barolong leaders was King Tau, son of Thibela, a mokhophe. King Tau, a warrior who reigned around 1660. He fought many battles and consolidated the Barolong tribe to become a very strong kingdom. He had many wives and begot many sons and daughters. The prominent four sons are Ratlou, Tshidi, Seleka, and Rapulana. The Barolong tribe later used the names of the warrior King Tau's sons as their clan names. The Barolong tribe spread across the regions covering Botswana through to Gauteng Province, Northwest Province, Northern Cape Province, and Free State in the current dispensation.
The eldest son of King Tau, Ratlou (of Barolong boo Mariba, known as Boo Tlou le Tau), resolved to reside in Ganyesa and reigned over a vast area in the current Kagisano and Molopo Municipalities in Dr. Ruth Segomotsi Mompati District, NW, South Africa.