Member states of the African Union
The member states of the African Union are the 55 sovereign states that have ratified or acceded to the Constitutive Act of the African Union to become member states to the African Union (AU). The AU was the successor to the Organisation of African Unity (OAU), and AU membership was open to all OAU member states.
From an original membership of 36 states when the OAU was established on 25 May 1963, there have been nineteen successive enlargements—the largest occurring on 18 July 1975 when four states joined. Morocco is the newest member state, having joined in January 2017. Morocco was a founder member of the OAU but withdrew in 1984 following the organization's acceptance of the Sahrawi Arab Democratic Republic as a member state. Morocco rules over most of the territory, but sovereignty is disputed.
As of 2017, the AU spans the entirety of the African continent, with the exception of Ceuta, Melilla, and Vélez de la Gomera. Also excluded are offshore islands that are integral parts of the transcontinental countries of France, Italy, Portugal, Spain and Yemen. The 55 member states are grouped into five regions, with the African Diaspora, structured as the State of the African Diaspora, known as the 6th Region