According to The Sopranos, A Family History, his father was Joseph "Beppo" Dante (Calabrian origin), a soldier who was "gunned down" in 1959. Silvio was a childhood friend of Tony and his early criminal activity often involved Tony, Ralph Cifaretto and Jackie Aprile, Sr. His original career plan was to be a professional singer, but this dream never materialized. Despite this, Silvio has maintained a connection to show business through ownership of numerous clubs in North Jersey over the years, and in backing aspiring young starlets who come up through his clubs. Silvio's profile in the DiMeo crime family began to rise following the robbery of Feech La Manna's card game alongside Jackie and Tony. He followed Tony into his father Giovanni Francis "Johnny Boy" Soprano's crew. Silvio's support was instrumental in ensuring Tony took over as Capo following his father's death. Throughout his association with the Soprano crew Silvio formed friendships with Salvatore "Big Pussy" Bonpensiero and Paulie "Walnuts" Gualtieri. Silvio's Al Pacino impressions were a constant source of amusement for the crew and he fancies himself a player in the entertainment world. He dresses carefully and has an encyclopedic mind for movies.
It was Silvio who reported to Tony that his Uncle Junior planned to murder Pussy Malanga' in Artie Bucco's restaurant and who was later entrusted with starting the fire which would ensure the original Vesuvio's burnt down, therefore not ruining its reputation. In the short and bloody war of 1999 with the Junior Soprano crew Silvio helped Tony to plan hits on Chucky Signore and Mikey Palmice and remained supportive when his friend revealed that he had been seeing a therapist. Silvio is one of the more level-headed associates of Tony Soprano. Where many of Tony's men immediately become hot-headed and resort to violence, Silvio generally helps to mediate many situations and gets along with everyone. He accompanies Tony to most of his "sit-downs" - a formal venue in the organization to resolve disputes. Because of this, Tony relies on Silvio to be a clear-headed thinker and someone he can trust. Silvio's move to consigliere once Tony became acting boss seemed completely natural. Indeed, Silvio remains Tony's most reliable adviser and enforcer, and tends to confine aggression to mob hits and poker games. However, over a remark made by Fat Dom about the no longer living Vito and implication that Carlo was gay, Silvio flipped out and in a burst of rage, attacked Dom. This led to Dom's death, as Silvio and Carlo beat and knifed him in a fit of passion. Despite Silvio's relatively even temper, he is also known for his bad behavior, foul mouth and paranoia when playing poker. Silvio's criminal interests include loan-sharking and bookmaking. Pandering could also be included among his criminal activities as inferred by his "management" roles at the Bada Bing.
Silvio's day-to-day role is that of managing the Bada Bing, the most recent in a string of strip clubs that he has operated. "The Bing," as members of Tony's crew often refer to their favorite hangout, is not only one of the crime family's major meeting spots, but also doubles as a brothel. The most notable instance of Silvio's club doubling as a house of prostitution is perhaps episode 3:32, University, where Silvio's role in this arrangement is especially poignant. Ironically, despite his misogyny, Silvio is also a strong father for his teenage daughter, Heather whom he calls The Principessa. When his daughter's soccer coach was found to be involved with one of his young players Silvio looked for vengeance but followed Tony's decision to let the authorities deal with him. Again ironically, apart from periodic instances of adultery, it can be said that he also loves his wife, Gabriella, very much.
Silvio has a long record of executing traitors throughout the show. He whacked Jimmy Altieri at the end of season one. Later, along with Tony and Paulie Walnuts, he executes Salvatore "Big Pussy" Bonpensiero in season two. In season five, he executes Adriana La Cerva. They were all killed when they were discovered to have been cooperating with the FBI in their ongoing investigation of the DiMeo Crime Family. Bonpensiero's killing haunted Silvio and he once dreamt he discovered his corpse in the dancers' room at the Bada Bing. In Season 6 Silvio also executed Burt Gervasi, by garroting him, after he discovered that he had been working with the New York Family.
Silvio's judgment wavered a little when he realized Tony was positioning Christopher Moltisanti as an intermediary between him and the rest of the organization because of their family connection. This was made most apparent when Paulie was arrested on a gun charge and Tony made Christopher acting capo of his crew in his absence. Sil responded by encouraging Gualtieri crew soldier Patsy Parisi to steal from the Esplanade construction site against Tony's and Chris' orders - creating problems for Chris. Silvio also became embroiled in a conflict over a Columbus Day celebration with Native American protesters - something Tony saw as a distraction - going so far as to get many of the family's associates involved in a violent altercation with the protesters. Silvio found it hard to let the conflict die even once Tony had exhausted all avenues of winning the dispute. Silvio did not take this uncharacteristic behaviour any further and, although Tony had noticed it, nothing came of it. Silvio got a chance to vent his frustration with Christopher at an intervention for his drug problem that ended with Chris being violently put in his place by Paulie and Silvio. Since Chris returned from rehab his relationship with Silvio seems to have returned to their previous friendly association.
Silvio maintains a realistic relationship with Paulie Gualtieri, well aware of his tight fisted attitude to money and dangerous tendencies. Silvio has remarked to Tony that they know that Paulie does not kick up his full tribute. Silvio also tried to warn Paulie that his distractedness had been noticed at the time when Paulie let his loyalties waver towards the Lupertazzi Crime Family, not long after Silvio's own crisis of faith in Tony. Paulie and Silvio argued about this --- Paulie had been harboring resentment for Silvio since an illness got Paulie into the Pine Barrens fiasco while making Silvio's rounds. However, it was not long before Paulie returned his attention to staying in Tony's good graces.
Silvio counseled Tony through difficult decisions about Richie Aprile, and his disputes with Ralph Cifaretto, Feech La Manna and Tony Blundetto. He is sometimes forced to convince Tony to go against his impulses - something that he usually manages without setting off Tony's hair-trigger temper.
When Tony ends up in a coma after being shot by his uncle in a fit of dementia, it falls upon Silvio to take the reins as acting boss of the DiMeo Family. At first, Silvio seemingly enjoys the job, and even feels a slight bit of regret that he did not accept an offer from the late Jackie Aprile, Sr. to become the boss back in the late '90s. His wife Gabriella prompts him to consider the possibilities of a permanent change. His ambitions quickly subside when he feels the immense pressure of being boss and begins to have asthma attacks. After a dreadful week of being hounded and pestered, coupled with the strain of worrying about his dear friend Tony, Silvio suffers an asthma attack brought on by anxiety. As boss Silvio dealt effectively with Paulie in a dispute over the split of profits from a heist Paulie had undertaken following a tip from capo Vito Spatafore. However, Silvio was indecisive in his handling of a dispute between Vito and Bobby Bacala over a collection route.
Since his return to the more comfortable role of Consigliere Silvio has again counseled Tony about contentious issues. When Vito was outed to the organization, Silvio convinced Tony of the need to restrain his desire to "give him a pass" because of the effect it would have on the other captains' view of his leadership. When Tony responded with distasteful jokes to Bobby Bacala's serious injury a look from Silvio was enough to tell him he was being unfair.
When Vito Spatafore came back from New Hampshire, Silvio said that there would be popular sentiment to get rid of him, but Tony had initially decided to let Vito run a prostitution ring in Atlantic City. However when Phil Leotardo confronted Tony about Vito being in New Jersey, Silvio and Tony both knew that they couldn't keep fighting with Phil over the issue and that if they wanted to keep the "no show" jobs Vito would have to go. Silvio had always pushed for Spatafore to be taken care of and told Tony that it was the right move and not to beat himself up over the issue. Silvio then instructed Carlo Gervasi to take care of Vito.
When Phil Leotardo and his men killed Vito (without the permission of the New Jersey Family), Tony told Silvio that it wasn't about Vito it was about him. Silvio initially told Tony that they should go after one of Phil's men but Tony was trying to avoid a war and instead decided to blow up Phil's wire room in Sheepshead Bay.
Silvio and Carlo were at Satriale's Pork Store later that day when "Fat Dom" Gamiello came by. Dom started making jokes about Vito's homosexuality and implied that Carlo was homosexual. Silvio told Dom to get out, but when Dom said "Carlo's lipstick was on Vito's cock," anger got the better of the usually calm consigliere as he smashed his hand-held vacuum over Dom's head and held him while Carlo stabbed him to death. A short time afterwards, Tony came by the shop to see them. Silvio advised Tony not to enter, but he couldn't stop Tony from finding Dom. Tony stormed out of the shop with Silvio right behind him telling Tony that "when you kill a made guy this is what happens."
In the episode "Stage 5" Silvio was out at lunch with Gerry Torciano, the man Phil Leotardo wanted to take over as boss of the New York Family, when one of Doc Santoro's assassins killed Torciano. This outraged Tony, as Silvio could have been hurt during that altercation.
In the episode "The Blue Comet", it is revealed that the Lupertazzi Family has recruited Burt Gervasi to begin a rebellion against Tony. Burt goes to Silvio to join in a coup d'état against the boss, but Silvio responds by strangling him to death at his home a short time later. Eventually assassination plots are put on Silvio, Bobby Bacala, and Tony Soprano in order to decapitate the leadership of the family. Shortly after Bobby is killed, while Patsy Parisi drives Silvio outside of the Bada Bing club, a car moves in front of them, with two men coming out shooting multiple times. Silvio tries taking a pistol out of the backseat, only to be shot in the back. Silvio manages to grab his pistol in time while Parisi holds them off. Parisi manages to defend them shortly, but soon the two men begin to target Dante more. He is shot once more in the chest, while Patsy runs into the woods, fleeing for his life. Afterwards, Silvio is rushed to the hospital and put in an intensive care unit.
Paulie Walnuts later tells Tony that Silvio managed to survive the assassination attempt but is in a coma; the doctors say that he isn't likely to recover consciousness. Tony later visits Silvio in the hospital. He says nothing, but holds his hand for a few moments. Silvio's fate beyond this is left unexplained.