Angelo Annaloro was born in Sicily, Italy, on May 21, 1910, and emigrated to the United States in his early teens, settling in Philadelphia, Pennsylvania. Due to the large influx of immigrants, especially Italians, throughout the 1900s, organized crime was well established in several large cities. In particular, the Philadelphia mafia family dated back to 1911. Salvatore Sabella, who also emigrated from Sicily, was the active boss in Philadelphia while Annaloro was becoming acquainted to his new life in the States. He was first introduced to Sabella by an associate of the Philadelphia crime family, Michael Maggio, who owned and operated a cheese factory where Angelo Annaloro worked as a salesman. Maggio had put in a good word to Sabella regarding Bruno's hard work ethic and shortly thereafter, Angelo Bruno was running several small time rackets, errands, and bootlegging operations for the crime boss. Sometime during his thirties, Angelo Annaloro officially became a "made" member of La Cosa Nostra, literally "this thing of ours."

After Sabella's death, Joseph "Bruno" Dovi took the the reigns as the active boss who was then succeeded by Joseph Ida. Ida was forced to relinquish his title as boss since he was to be deported back to Italy. He was to choose between Angelo Annaloro and Antonio Pollina, as both men exhibited loyalty and were top earners for the family. Pollina was chosen over Annaloro, though he still considered Annaloro his competitor and sought to have him murdered. He put in an order to have him "whacked" but never received permission from the mafia commission which is comprised of the head members of all the families including the bosses in New York and New Jersey. Pollina faced much scrutiny especially because Annaloro had established a close friendship with Carlo Gambino, a very powerful and fierce boss who ran the New York City family, as the two were partners in a land contract in Florida. Gambino was extremely angered by Antonio Pollina's ignorance. As a result, Angelo Annaloro was named the new boss of the Philadelphia family in 1959. He then became known as Angelo Bruno as he assumed the surname of previous reigning boss Joseph "Bruno" Dovi.

Angelo Bruno was well known for instituting order and increasing the power of the Philadelphia mob family and connections to larger, more established families in New York and New Jersey. Bruno was accredited with upholding traditional mafia business such as loan sharking, extortion, racketeering, etc. He was also given the nickname of "The Gentle Don," as he preferred to reconcile any disputes in a more professional and non-violent manner. Bruno's twelfth year as boss in 1971 marked the occasion of being the longest serving boss of the Philadelphia family and was quickly getting his family recognized. Then in 1976, Atlantic City, New Jersey, passed legislation to make gambling legal and rushed to construct casinos. Bruno saw a great business venture with the enactment of the new laws and used his connections with several steel companies in Pittsburgh to demonstrate an authoritative yet lending hand in the construction of the casinos in Atlantic City. Having done so, Bruno held a strong position in New Jersey as he was a major contributor to the building and then operation of the casinos which further elevated the power and reputation of the Philadelphia family.

Angelo Bruno's family was receiving a large profit from the revenue of the casinos in New Jersey. Despite money coming in from New Jersey, several young captains and soldiers were becoming resentful because Bruno refused to take part in the lucrative trafficking of narcotics. The fuel of greed and appeal of fast money from drugs was angering his crew but they soon expressed further discontent in 1977 when New Jersey altered their gambling laws, forcing Bruno to decrease his activity and declare the casinos as open territory; this then allowed for the New York and New Jersey families to acquire more money as Bruno was not as influential. However, he maintained power and was bringing in large sums of money for his family through other traditional business enterprises.

Throughout Angelo Bruno's career as mob boss, he managed to avoid media attention and harassment of law enforcement officials as he eagerly tried to deter violence and association with narcotics trade. He had approximately thirteen arrests for acts such as loan sharking, interstate tax conspiracy, false income tax returns, etc. However, when Bruno was sixty years old, he was imprisoned for two years in New Jersey for refusing to testify before a grand jury during an investigation of Atlantic City corruption, involving several high ranking officials. After various run-ins with the law, the looming despondence of the Philadelphia mafia family was rising to an all time high and Bruno's consigliere, Anthony Caponigro, conspired with the heads of the New York and New Jersey families to eliminate Bruno.

The hit by Anthony Caponigro was eventually carried out on March 21, 1980. John Stanta, one of Bruno's soldiers and drivers, returned the boss home where he was brutally murdered, suffering a shot gun blast to the back of his head in front of his South Philadelphia home. Angelo Bruno was sixty-nine years old. Caponigro's plan of action backfired as he did not receive full permission to follow through with the murder and was not appointed the new boss of the family as he had hoped and Phillip Testa took charge. Angelo Bruno was laid to rest and is buried at the Holy Cross Cemetery in Yeadon, Delaware County, Pennsylvania. Soon after the death of "The Gentle Don," the Philadelphia mob was left in shambles; as many as thirty mobsters were murdered and greed, betrayal, and convictions through the use of informants plagued Philadelphia's once flourishing families. Ultimately, the peace ended after Angelo Bruno was killed and the Philadelphia mob family became known as the most dysfunctional mafia family in the United States.