Short answers, pulled from the story.
The Italian Socialist Party was established on the 14th of August 1892 in Genoa. Delegates gathered to form the Party of Italian Workers which later became a century-long political force.
Filippo Turati emerged as a key figure during the formative years while Pietro Nenni guided the party through turbulent post-war years. Bettino Craxi served as party secretary from 1976 until the scandals of the early 1990s.
The Livorno Congress of 1921 marked an irreversible fracture when the left wing broke away to form the Communist Party of Italy. Another split occurred in 1922 when reformists headed by Giacomo Matteotti were expelled and created the Unitary Socialist Party.
Mario Chiesa was caught taking bribes in February 1992 triggering chain reactions throughout the political system via mani pulite investigations. Public opinion turned decisively against the party as probes expanded to ministers and leaders leading to its dissolution in 1994.
Socialist organizations originated earlier in Northern Italy with strongholds in Emilia-Romagna, Lombardy, and Piedmont. Electoral percentages reached extremes like 60 percent in Novara and over 70 percent near Bologna and Ferrara during peak periods.