Andrea Antonio Baldassarre Costa (30 November 1851 – 19 January 1910) was an Italian politician, Master Mason and socialist activist, born in Imola. Initiated in September 25 1883 to the Masonic Lodge "Rienzi" in Rome, he progressively become 32nd degree Mason and adjunctive Great Master of the Grande Oriente d'Italia. He co-founded the Partito dei Lavoratori Italiani in 1892 after renouncing his anarchist principles in 1879. It is probable that this happened due to his marriage to Russian Socialist Anna Kulischov. In his later years Costa was an active politician; he served as mayor of Imola and as a representative in the Italian Parliament. He died in Imola in 1910. His close friend and masonic brother Giovanni Pascoli wrote the funeral inscription dedicated to him, whom he knew together with Alceste Faggioli when he was a university student.
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- "The epitaph of Andrea Coosta (written by Giovanni Pascoli)". loggiagiordanobruno.com (in Italian). Retrieved Sep 23, 2018.
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- R. Boschetti. "Giovanni Pascoli: portrait of a young socialist poet". storiain.net (in Italian). Archived from the original on May 21, 2018. Retrieved Sep 23, 2018.
- Centenario della morte di Andrea Costa – Biography
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