African Union (AU)
History. The Fourth Extraordinary Session of the Assembly of the Heads of State and Government of the Organization of African Unity (OAU) held in Sirté, Libya on 9 Sept. 1999 decided to establish an African Union. At Lomé, Togo on 11 July 2000 the OAU Assembly of the Heads of State and Government adopted the Constitutive Act of the African Union, which was later ratified by the required two-thirds of the member states of the Organization of African Unity (OAU); it came into force on 26 May 2001. The Lusaka Summit, in July 2001, gave a mandate to translate the transformation of the Organization of African Unity into the African Union, and on 9 July 2002 the Durban Summit, in South Africa, formally launched the African Union.