The brutal repression of the military regime in El Salvador has forced opposition to armed resistance. Between 1980 and 1991, 70,000 people, mostly civilians, were killed in the civil war. More than a million people fled the country. Guerrilla groups made up of Communists, Christians and trade unions have united in the FMLN (Frente Farabundo Martí para la Liberación Nacional).
The US government supported the military dictatorship in El Salvador. In addition to sending military advisers, the US rehearsed the Bataillon Atlacatl anti-guerrilla unit responsible for the 1981 massacre of 900 civilians in El Mozote. It was one of the greatest war crimes in Latin American history. The then US foreign secretary, Alexander Haig, called El Salvador a trial field for the Cold War.
The Reagan government was aware of the systematic killings of 40,000 opposition members, ordered by the Salvadoran government in the early 1980s. After that, relative peace prevailed, and the US boasted that successful reform of the country had led to general peace. The grave violations of human rights led to the formation of church circles that spoke openly against such foreign policy, but to no avail. The church has not been so engaged since the Vietnam War. The impetus for public speaking was the murder and rape of American priests, missionaries, monks, and nuns.
In early 1992, the Catholic Church and the UN brokered peace talks between FMNL and the Salvadoran government. Peace was signed at Chapultepec Castle in Mexico City on January 16, 1992, and an armed truce came into force on February 1. The peace treaty defines the transition to democracy.