Soccer arrived in Latin America in the 1800s. In the beginning it was primarily played by affluent Europeans, but was soon adopted by people from all socio-economic classes bridging the divide between the ruling elites and the indigenous population.
As a cultural institution, it quickly became synonymous with national identity and disputes on the field of play frequently resulted in violence between players, fans, and in extreme cases even countries.
The visible displays of nationalism include flag waving, national anthems, even colorful clothing. They are an expression of the emotional attachment that individuals feel for their teams. So when deliberate physical injury to a player or perceived bias by referees alter the outcome of games, fan violence is inevitable. Add to that political tensions between the governments of the competing teams, and international competitions have even led to war. Such was the case in 1969 between the neighboring Central American countries of El Salvador and Honduras.
The Soccer War (sometimes referred to as the 100 Hours War) was fueled by extreme national pride. Violence erupted between fans during the first two 1970 FIFA World Cup qualifying matches. The teams split the first two contests spawning yet greater tumult between the two fan bases as the third and deciding match approached.
Tensions had been building for months between the two governments over new immigration laws in Honduras that stripped land ownership from Salvadoran citizens settling in that country. The expulsion of over eleven thousand such immigrants and migrant workers just happened to coincide with the timing between the first and second games. Citing Honduran nationalism and fan violence as the reason for its action, El Salvador severed all diplomatic ties with its neighbor and deployed soldiers onto Honduran soil.
The war was brief, beginning on July 14, 1969, and ending on July 20, 1969, with a cease-fire negotiated by the Organization of American States (OAS). El Salvador initially demanded that Honduras agree to reparations for those Salvadorans who had been displaced and assurances of fair treatment for those settlers who chose to remain. It finally withdrew its forces on August 2, 1969, after promises of protection for its citizens on Honduran soil.
The dispute simmered long after the Salvadoran soccer team defeated Honduras 3-2 in the final qualifying match in Mexico City and long after cessation of hostilities between the two armies. A final peace treaty would not be signed until October 30, 1980. — Excerpt from Tarnished Brass.