Born in, Loures, Lisbon District, Jerónimo de Sousa was born into a humble working-class family, dominated by the right-leaning regime of António de Oliveira Salazar. At the age of 14, he followed the path of most of the children of the working-class families growing up in the industrial belt of Lisbon. He became a machine tuner in a siderurgy near his hometown. He started his anti-fascist activities soon after, while integrating the cultural working class associations of his hometown in the 1960s. In that period he made contact with the strong clandestine organization that the Portuguese Communist Party had in the suburbs of Lisbon, where he, being one of the few able to read, used to read the illegal communist newspaper Avante!, in secrecy, for the other workers. He would later formalize his membership, right after the Carnation Revolution, in 1974. From 1969 to 1971 Jerónimo de Sousa participated in the Colonial War against the liberation movements that were struggling in the Portuguese colonies in Africa. He served in Guinea-Bissau, forced to fight the Marxist movement of liberation, the PAIGC. After the replacement of Salazar by Marcello Caetano in 1969, the regime made some slight democratic openings, one of them was the possibility of workers without any record of illegal political activity participate in the elections for the respective Unions. In 1973 he participated in the election for the leadership of the Lisbon Metallurgical Workers' Union, dominated by the collaborationists of the regime, a characteristic of the corporativist regime of Salazar. Being free of any political suspicion and after being chosen among the MEC workers to integrate the list to the Lisbon Union, he was able to participate in the election and his list, influenced in secrecy by the communists, won it. From April 1974 he was elected to the workers commission of MEC, a role he kept until 1995.
Activity after the Carnation Revolution of 1974
In the first democratic election after 48 years of country's history, that was meant to elect a parliament that would write a new democratic constitution, Jerónimo de Sousa was elected as MP. Entering the Assembly of the Republic for the first time, a curious thing happened: a worker at the Assembly called him "doctor", he answered he was not a doctor and the worker replied: "sorry engineer", expressing the weirdness associated with the presence of a factory worker in a chamber that was dominated for 48 years by the top figures of the regime. He continued to be elected in the subsequent legislative elections, and only left parliament in 1993. In 2002, he returned after the legislative election of that year. Meanwhile, Jerónimo was elected for the first time to the Central Committee of the PCP in 1979 and became a member of its Political Bureau in 1992. He was the Party's candidate for the 1996 presidential election, but he left the race giving his support to the Socialist candidate, Jorge Sampaio. In 2004, after the Party's 17th Congress, in November, Jerónimo de Sousa was elected General Secretary, replacing Carlos Carvalhas. He was announced as the Party's candidate for 2006 presidential election, and also gathered the support of the Ecologist Party "The Greens".
