La Violencia refers to the ten-year period of civil war in Colombia between 1948 and 1958. Following the assassination of the populist/liberal and very popular presidential candidate Jorge Eliecer Gaitan on 9 April 1948, rioting erupted in Bogota, referred to as the Bogotzo riots. During the ten-hour riot an estimated 3,000 to 5,000 people were killed and much of Bogota was destroyed. The violent clashes that erupted between members of the Conservative Party and members of the Liberal Party, quickly became La Violencia, a civil war that would last ten years.
Much of La Violencia was fought in rural areas. In 1946 conservatives had returned to leadership who then, with the rural police, encouraged conservative peasants to take land from rural liberal peasants. Over the ten-year war, an estimated 200,000 people were killed and millions more fled their land and homes as the parties fought for control of the nation's agricultural land.
During La Violencia, censorship against liberals and media members was draconian, very little reporting on the violence was published and many fled the country. In 1950, no liberal candidates ran for any office.
Paramilitary forces made up of supporters of the Communist Party and the Liberal Party fought against the Conservative Party forces throughout La Violencia, a form of guerilla violence that continues even today in Colombia in the form of organizations such as FARC and ELN. When General Gustavo Rojas Pinilla took power in 1953 he demobilized these forces, though not all leaders agreed and violence continued until Rojas was removed from power in May 1957 when civilian rule was restored.
Moderate conservative and liberal leaders formed a coalition that came to be called the National Front, supported as well by some members of dissident segments of the military. Alberto Lleras Camargo's government made changes to governmental power structures that allowed for sharing of power between the parties and presidents alternating between the parties. The last of the bandolero leaders were killed, still fighting the army, in 1965.