During this time radical ideas were spreading in Bolivia and the Movimiento Nacionalista Revolucionaria or MNR was formed. In 1943 the MNR formed an alliance with some army officers and they staged a coup. Gualberto Villaroel led the new government. However Villaroel was overthrown by a revolution in 1946 and he was hanged outside the presidential palace. Bolivia was then ruled by a coalition of traditional parties until 1951 when the army took control.
However in 1952 the MNR launched a revolution and returned to power. They then embarked on a programme of reform. The three biggest tin companies in Bolivia were nationalized and universal suffrage was introduced (everybody was given the vote).
However in the mid-1950s Bolivia suffered from high inflation. Faced with economic troubles the Bolivian government turned to the USA for help. The USA gave loans and the economy stabilized but in 1964 the army staged another coup.
For most of the next 18 years Bolivia endured military dictatorship. Despite the repression the Bolivian economy boomed and the population grew rapidly. However in the early 1980s the economy took a downturn. Faced with mass demonstrations and international condemnation the last junta stepped down and congress was restored. In 1982 Hernando Siles Zuazo became president.
However during his reign Bolivia suffered major economic problems including raging inflation and he stepped won in 1985. His successor Paz Estenssoro managed to curb inflation but in 1989 he was replaced by Paz Zamora. Gonzalo Sanchez de Lozada replaced him in 1993. He undertook a privatization campaign and under him the Bolivian economy grew.
However the Bolivian economy flagged from 1999 but it began to grow again in 2003.
In 2005 left-wing Evo Morales was elected president with plans to nationalize industry.
Today Bolivia remains a poor country but it is rich in resources. Perhaps its greatest resource is tourism and it has beautiful scenery and wildlife.