Treaty of El Pardo (1778)

The Treaty of El Pardo signed on 11 March 1778 sought to end conflict between Spain and Portugal in the Río de la Plata region, along the modern boundary between Argentina and Uruguay. It confirmed Spanish ownership of Colonia del Sacramento, now in Uruguay, while Portugal ceded possession of strategically important territories in Africa, now the modern state of Equatorial Guinea.

Source: Wikipedia — Treaty of El Pardo (1778) (CC BY-SA 4.0)