The Sandinista Front for National Liberation or SFNL was a Nicaraguan political party formed in opposition of the Somoza dictatorship from 1936-1979. The SFNL was in part named after a Nicaraguan anti-imperialist patriot named Augusto Cesar Sandino. Sandino fought a seven year war against U.S. occupation in Nicaragua (1926-1933). Augusto was killed while unarmed by the orders of Anastacio Somoza Garcia who was the head of the U.S. formed Nicaraguan National Guard.
In 1936 Somoza destroyed the civilian government and rose to presidency by rigging the election. This was the beginning of the Somoza dictatorship. From 1936 until 1979 Somoza, his two sons Luis and Anastacio Jr., and a cronie were the only rulers of Nicaragua.
Carlos Fonseca, Silvio Mayorga and Tomas Borge among others were the founders of the SFNL though Carlos was seen as the intellectual father of the party. His revolutionary ideology is now referred to as Sandinismo. Sandinismo is a mixture of certain Marxist concepts, nationalism, and anti-imperialism, all of which in the context of 20th century Nicaragua.
The Sandinistas began plans for a military overthrow once it became clear that Somoza was not hearing their peaceful protesting. During the next decade the Sandinistas became depleted by their combat with Somoza, and by the early 70’s all of the founding members, save Borge, had been killed. They decided to go underground for a while to build up their strength and get more organized politically. During this time, they created 3 factions: The Prolonged Popular War Tendency, which prioritized gaining support from the grassroots, agrarian lower class populous, the Proletarian Tendency, which prioritized supporting union workers to form defense units, and the Terceristas, whose goal was to unify all citizens against Sozoma and create a national insurrection.
The insurrection began late 1978. By July 1979 Anastacio Jr. was overthrown.
Now in power, the Sandinistas began on intense reform of the country on both an economic and a political level. They pulled Nicaragua out of underdevelopment and into democracy. They reformed institutions and disbanded the Nicaraguan National Guard.
The first ever democratic election in Nicaragua occurred in 1984, the Sandinistas won by 66%. By 1987 the Nicaraguan Constitution was completed and the Sandinistas began redistributing the land confiscated from Somoza and his cronies (20% of arid land in the country). It was distributed between individual peasants, cooperatives, and collective farms.