The Irish gang were a group of Irish criminals from Hell's Kitchen.
In 1933, the O'Rourke brothers attempt to assassinate Luca Brasi, the plan is abandoned when Brasi and his gang arrive together however Willie decides to still attempt to kill Brasi but only wounds two of Brasi's men. this leads to Brasi murdering three of Tomasino Cinquemani's men before learning the Irish were responsible after the Irish raid the Brasi gangs gambling den. Brasi retaliates by blinding Donnie and killing Willie.
In 1934, the gang attempt to hit Vito Corleone during the Parade, this leads to a firefight, Stevie Dwyer attempted to shoot Corleone, and was foiled by Bobby Corcoran, who accidentally hit Vito himself. During the shoot out Stevie Dwyer, Peter Murray, and Sean O'Rourke are all killed. while the others flee.
- Donnie O'Rourke - founder and leader of Irish Gang
- Ricky Donnelly - second-in-command
- Willie O'Rourke
- Billy Donnelly
- Peter Murray
- Corr Gibson
- Stevie Dwyer
- Terry O'Bannion
- Digger McLean
- Sean O'Rourke