Bowery Boys

The name The Bowery Boys came from an anti-Catholic, anti-Irish gang formed in the Five Points district of New York City.

They were named The Bowery Boys because they lived mostly in the section called Bowery and one of their most famous members was William Poole, known as Bill the Butcher and made famous by Daniel Day Lewis' performance in Gangs of New York

Source: http://www.nowpublic.com/culture/bowery-boys-tcm-new-movie-every-saturday-morning-2587332.html