The Basutoland African Congress (BAC) was founded in 1952 by Ntsu Mokhehle and Potlako Leballo. The party was renamed the Basutoland Congress Party (BCP) in 1957 and retained this name after independence in 1966, stating that Lesotho was not truly independent. Leballo left the party in 1959 to form the Pan Africanist Congress of South Africa (PAC).
The BCP lost the 1965 election but won in 1970. It was denied power by a military coup in support of the defeated prime minister Leabua Jonathan Molapo.
In 1974, following an unsuccessful rising, the BCP sent 178 men for military training by the PAC in Libya. In 1979 they began a guerrilla war as the Lesotho Liberation Army (LLA).