This article analyzes relevant aspects of the appearance and consolidation of Protestantism in Costa Rica from the mid-19th century to 1980. We opted for a qualitative methodology and a socio-historical approach. Moscovici and his theory of “active minorities” constitute the theoretical reference. The sources consulted correspond to the historians Wilton Nelson, Arturo Piedra, Juan Stam and press releases. The first Protestant temple was built in 1865 in San Jose at the initiative of foreigners. However, the Costa Rican churches themselves belong to the Jamaican Baptist Church (1888), the Wesleyan Methodist Church (1894) and the Anglican Church (1896), all in Puerto Limón. Missionary efforts were aimed at evangelizing Costa Rica within the framework of a project for Central America; It was undertaken by the Central American Mission (1891), the Methodist Church (1917) and the Latin American Mission (1923). Their objective was to establish churches carrying their own religious capital, in addition to competing with Catholicism.