When in 1861 almost 200 liberated black Cubans located in Fernando Po's “Barrio Congo” for public construction labor, a language contact process started off. Four years later, a few hundred political activists were exiled from Cuba to Fernando Po given their possible impact in the Cuban revolution. This might have prompted Cubans’ and Afro-Cubans’ lexical transfers to the Spanish spoken in Fernando Po as product of the two-way link of the transatlantic slave trade. Using royal decrees, archival material and Cuban exiles' memoirs, this paper rebuilds the historical context of that language contact and debates the kind of intercolonial borrowings that spread on both sides of the Atlantic during the 19th century.