He succeeded Bill Lovett after his murder in 1923 and, under his leadership, led a two-year campaign against Frankie Yale over the New York waterfront until he and five of his lieutenants were killed in South Brooklyn during a Christmas Day celebration at the Adonis Social Club in 1925.
Believed by authorities to have been involved in at least a dozen murders during his criminal career, he was reportedly well known for his hatred of Italian-Americans and would occasionally lead "guinea hunting" expeditions in saloons and dive bars along the waterfront.
[citation needed] When three local Irish girls entered the club escorted by their Italian dates, Lonergan chased them out supposedly yelling at them to "Come back with white men, fer chrissake!
[citation needed] A fourth member, James Hart, managed to escape, having been found a few blocks away crawling on the sidewalk after being shot in the thigh and leg.
[2][3][4][5] Anna Lonergan publicly blamed the gangland shooting on "foreigners" commenting "You can bet it was no Irish American like ourselves who would stage a mean murder like this on Christmas Day".