While at Anthony Corleone's first communion part at Lake Tahoe in Nevada, Frank Pentangeli explained that he wanted the Rosato Brothers dead, while in a drunken state. Earlier, he had refused to give them any of their promised lands after the death of Peter Clemenza, a caporegime of the Corleone family. The Rosato Family and the Corleone family had possessions in New York, while Tony Rosato had to share Miami with the Granados crime family. Jewish mob boss Hyman Roth held a meeting in Havana, Cuba, to settle the mafia's future. The Corleones possessed the Hotel Capri, while the Rosatos had to share non-casino operations with the Almeida family. However, a scandal broke out when the resignation of Cuban president Fulgencio Batista caused a ruckuss in front of the estate that the meeting was held at. Since the plans for the families were interrupted, mob war was inevitable between the Rosato Brothers and the Corleone family. In the escape from Cuba, the Don of New York Aldo Trapani was killed by a communist sniper. The other Corleones barely made it to safety.
Six weeks after the escape from Havana, the Rosato crime family split from the Corleones and seized hostages and businesses. Michael Corleone, the head of the Corleone family, promoted Dominic to Don of Trapani family as well as Don of New York, which means he had to unite New York under the Trapanis and Corleones again, while Fredo Corleone took care of Aldo's mother. Pentangeli acted as an advisor to Dominic, and taught him about recruiting men. After making a man for his cause, Dominic took over Sweet Life Bakery and La Maison Rouge from Carmine Rosato in order to control the prostitution crime ring of New York City.
Carmine Rosato pretended to be defeated and called for a meeting with the Corleones at Richie's Tavern. He attempted to kill Pentangeli, and Dominic thought he was dead while escaping from the police and Rosato's men. He escaped by jumping over rooftops and escaping to his safehouse given to him by Michael Corleone. This meant that the war would still be in action. After hiring more soldatos for his family, he took over all of Carmine Rosato's businesses. This unlocked the compound of Rosato, and his soldiers killed him. His demolition expert Bill Bardi set a charge in the house and it exploded after Dominic's men had escaped from the scene.
Then, the Trapanis headed to Miami in order to fight Tony Rosato, the more intelligent of the two brothers. At the same time, Dominic started a war against the Granados family (main article: Trapani - Granados War). Tony Rosato was involved in two conflicts, and took over some of Rico Granados's businesses. Yet afterwards, the Trapanis and Corleones seized all of his rackets and the Corleones prepared a final assault on the Rosato compound in New York. After shooting dead all of Rosato's men and officers, Rosato was gunned down, and similar to his brother's fate, was killed by a bomb on the compound set by Bill Bardi. This ended the war with the Rosato brothers and exterminated their families.