This work deals with the participation of Christians in liberation struggles in Latin America during the 1970s and 1980s, specifically in the countries of Nicaragua and El Salvador. It analyses the emergence of Liberation Theology in Latin America, the dialogue between Marxism and Christianity and the positions taken by the Catholic Church in these contexts. In the case of Nicaragua, the work of the priest and poet Ernesto Cardenal, a member of the Sandinista Front and of the popular government that won in 1979, is used as a source. In El Salvador, we look at the dictatorial context and the resistance built up by the Basic Ecclesial Communities, using the experience of Dom Oscar Romero and his speeches to understand the process experienced in the country. The aim is to recover the memory of the resistance and struggles of the Latin American peoples in the face of dependent capitalism and US imperialism, and to problematise the role of the Catholic Church in this context.