[1] Born into a working-class family of Corticella, a district of Bologna (his father was a worker and the mother a housewife), Nesi participated in the partisan resistance and then graduated in law.
Profoundly Catholic, his first political experience was in the Christian Democracy, but a choice was not linked to ideological reasons but by the conformist spirit, since in his city, the Italian Communist Party (PCI) had 58% of the vote, while the DC trudged to 12% approximately.
He entered instead in the Italian Socialist Party, in the current driven by Riccardo Lombardi, whose political alignment lay further left.
Shortly thereafter he created the office of PSI Credit and Insurance (of which he was chief from 1977 to 1978) and continued his climb unabated: he was president of the Banca Nazionale del Lavoro (BNL) in the 1980s and until the fall of Berlin Wall, he worked as a business journalist at the RAI in Turin and as an engineer at Olivetti.
His relations with Bettino Craxi were not always positive and when in 1994 the PSI was gone, Nesi decided to join the Communist Refoundation Party with which he was elected in 1996.