The Football War was a brief war fought between El Salvador and Honduras in 1969. Existing tensions between the two countries coincided with rioting during a 1970 FIFA World Cup qualifier. The war began on 14 July 1969, when the Salvadoran military launched an attack against Honduras. The Organization of American States (OAS) negotiated a cease-fire on the night of 18 July (hence "100 Hour War"), which took full effect on 20 July. Salvadoran troops were withdrawn in early August.

In June 1969, Honduras and El Salvador met in a two-leg 1970 World Cup qualifier. There was fighting between fans at the first game in Tegucigalpa on 8 June 1969, which Honduras won 1–0. The second game, on 15 June 1969 in San Salvador, which was won 3–0 by El Salvador, was followed by even greater violence.

On 27 June 1969, the day the play-off match took place in Mexico City, El Salvador dissolved all diplomatic ties with Honduras, stating that in the ten days since the game in El Salvador 11,700 Salvadorans had been forced to flee Honduras. It said that as Honduras had "done nothing to prevent murder, oppression, rape, plundering and the mass expulsion of Salvadoreans", there was little point in maintaining relations.

Late in the afternoon of 14 July 1969, the concerted military action began. El Salvador was put on a blackout and the Salvadoran Air Force, using passenger airplanes with explosives strapped to their sides as bombers, attacked targets inside Honduras.

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