The Economic Community of West African States (ECOWAS) was established on May 28, 1975, with the signing of the Treaty of Lagos by fifteen West African countries. Its mission was to promote economic integration across the region. Cape Verde later joined in 1977, while Mauritania, one of the original members, withdrew in December 2000. ECOWAS aims to foster economic cooperation, collective self-sufficiency, and regional integration among its member states.