Sandinista
Between 1959 and 1963, Fonseca and those who would become the earliest members of the FSLN "experimented with a variety of different organizational forms" in the hopes of forming a true revolutionary organization. Having formed several short-lived groups, the FSLN came to be in 1963. Originally, Fonseca hoped to duplicate the Cuban revolution in Nicaragua, drawing up battle plans based on the Cuban experience.
In mid-1963, a guerrilla cadre entered the Rios Coco y Bocay area of Nicaragua. Poorly prepared and having done little advanced work in the area, several guerrillas were killed by the Guardia Nacional, while others were able to escape across the Honduran border. This incident would highlight the error of having an "excessive emphasis on military actions without corresponding political work".
In June 1964, Fonseca and Víctor Tirado were arrested in Managua. The two (along with four others) were accused of plotting to assassinate Anastasio Somoza Debayle. Rather than present a defense during his trial, Fonseca leveled charges against Somoza which were later detailed in his manuscript, From Prison, I Accuse the Dictatorship.
Between 1964 and 1966, the FSLN "concentrated on educational work and community organizing", creating indoctrination classes and campaigning to bring resources to working-class neighborhoods in Managua. While Fonseca continued to hold the top leadership position in the FSLN, he was out of the country for much of the mid-1960s period, having fled to Mexico and then Costa Rica.
By mid-1966, plans for a second FSLN guerrilla operation in the Pancasan region (near Matagalpa) were underway. The operation began in May 1967 with about forty guerrillas. This time, the guerrillas were better trained and armed, and more interestingly, had women among their ranks. Fonseca, along with a few other FSLN leaders were "committed to the idea of including women", however, some of the other fighters were not comfortable fighting alongside women.
Like the earlier guerrilla incursion, the Pancasan operation ended with many of the FSLN guerrillas being wiped out by the Guardia Nacional. However, Fonseca, and the others that survived, considered the operation a political victory "because it showed the whole country that the FSLN still existed".
According to Vasili Mitrokhin, Fonseca was a KGB agent. In his book The World Was Going Our Way, Mitrokhin relates how, as part of Aleksandr Shelepin’s strategy of using national liberation movements to advance the Soviet Union's foreign policy in the third world, Shelepin organized funding and training in Moscow for twelve individuals that Fonseca handpicked, and the twelve were the core of the new Sandinista organization. However, UCLA historian J. Arch Getty, whose specialty is Russia, writing in the American Historical Review, raised questions about the trustworthiness and verifiability of Mitrokhin's material about the Soviet Union, doubting whether this "self-described loner with increasingly anti-Soviet views" would have had the opportunity to "transcribe thousands of documents, smuggle them out of KGB premises", etc. Former Indian counter-terrorism chief Bahukutumbi Raman also questions both the validity of the material as well as the conclusions drawn from them.
Read more about this topic: Carlos Fonseca