Presidency of Salvador Allende in the context of Military dictatorship of Chile (1973–90)

An authoritarian military dictatorship ruled Chile for almost seventeen years, between 11 September 1973 and 11 March 1990. The dictatorship was established after the democratically elected socialist government of Salvador Allende was overthrown in a coup d'état backed by the United States on 11 September 1973. During this time, the country was ruled by a military junta headed by General Augusto Pinochet. The military used the breakdown of democracy and the economic crisis that took place during Allende's presidency to justify its seizure of power. The dictatorship presented its mission as a "national reconstruction". The coup was the result of multiple forces, including pressure from conservative groups, certain political parties, union strikes and other domestic unrest, as well as international factors.

The regime was characterized by the systematic suppression of political parties and the persecution of dissidents to an extent unprecedented in the history of Chile. Overall, the regime left over 3,000 dead or missing, tortured tens of thousands of prisoners, and drove an estimated 200,000 Chileans into exile. The dictatorship's effects on Chilean political and economic life continue to be felt. Two years after its ascension, neoliberal economic reforms were implemented in sharp contrast to Allende's leftist policies. The government was advised by the Chicago Boys, a team of free-market economists educated in the United States. Later, in 1980, the regime replaced the 1925 Constitution with a new constitution in a controversial referendum. This established a series of provisions that would eventually lead to the 1988 Chilean national plebiscite on October 5 of that year.

El Teniente (Spanish for "The Lieutenant") is the world's largest underground copper mine, located in the Andes Mountains of central Chile at an elevation of 2,300 metres (7,500 ft) above sea level. It is operated by the state-owned mining company Codelco and constitutes the largest division of its operations. Mining at the site dates back to at least 1819, but large-scale industrial extraction began in 1906 under U.S. ownership, initially through the Braden Copper Company and later Kennecott Copper Corporation. In 1971, during the presidency of Salvador Allende, Chile nationalized its copper industry and acquired full ownership of El Teniente. The mine contains more than 3,000 kilometres (1,900 mi) of tunnels and employs about five thousand workers. It was the site of the 1945 Smoke Tragedy, the deadliest metal mining accident in Chilean and world history. Since 2011, El Teniente has been undergoing a major expansion known as the New Mine Level project, which aims to extend operations deeper into the mountain without halting production. As of 2023 it is the third most productive copper mine in Chile after Los Pelambres and Escondida.