Lionele Tommasino was an old friend of Vito Corleone who lived in Vito's native village of Corleone, Sicily. He was believed to be the elder brother of Carmela Corleone. He was portrayed by Corrado Gaipa, Mario Cotone and Vittorio Duse.
When Vito returned to the village of Corleone in the 1920s looking to exact revenge on Don Ciccio for the latter's role in the murder of his parents, Tommasino assisted him in his scheme. However, during the murder attempt, Tommasino was crippled by a blast from a lupara shotgun, fired by one of Don Ciccio's bodyguards. Still, despite his disability, Tommasino succeeded Ciccio as the local Mafia chieftain of the town of Corleone, and maintained his strong friendship with Vito. When Vito's son Michael Corleone murdered drug lord Virgil Sollozzo and corrupt NYPD captain Mark McCluskey in the late 1940s, he was immediately dispatched to Sicily and placed under Tommasino's care; Tommasino ensured that Michael was safe from both the police and his enemies, and put him up in the house of his uncle Dr. Taza. At this time, Tommasino was having trouble with the 'gavoones' in Palermo, the new regime of Dons who had no respect for the old order and were initiating wave after wave of vendettas. Because of this, the Don was absent for much of the time Michael spent there. However, he did give his blessing for Michael to marry Apollonia Vitelli in 1948, and it was largely his friedship with the groom that convinced to Signor Vitelli to allow his daughter to be courted. However, Tommasino's man, Fabrizio, turned out to be a traitor and attempted to assassinate Michael with a car bomb and killed Michael's new wife instead. After this, it was decided Sicily had become too dangerous for Michael and he was moved back to New York. Despite this unfortunate incident, Tommasino maintained a close friendship to the Corleones. In 1979, Michael returned to Sicily to seek the elderly Tommasino's advice about making contacts in the Vatican, in order to aid in his takeover of the Italian conglomerate Immobiliare. However, that same year, Tommasino was assassinated by the hitman Mosca, who had been hired by Don Altobello to kill Michael. Mosca had disguised himself as a Roman Catholic priest and was walking down the road with an associate of his who was dressed similarly. Tommasino pulled up in his car and offered Mosca a ride, but instantly recognized him for who he was. His cover blown, Mosca shot Tommasino dead with a lupara hidden in his robe. Tommasino's death made Michael attempt to repent of his former life and hand over the Family and the responsibility that went with it, to Vincent Mancini.