The first reported Mafia killing in the United States took place in New York City, of course, in an Italian restaurant, of course, and it occured in 1888.
But it wasn’t the FirstMention of The Mafia. That honor belongs to a New York Times article dated May 27, 1877, and titled (of course) “The Mafia”. [But see addendum, below]
|The Mafia.–In Sicily the Mafia is the spontaneous organization of those whose trade is crime; not a sect or secret society, any more than the highwaymen of Hounslow in former days, or the pickpockets of St. Giles’ and Whitechapel in our own. Every one of the 350 communes of Sicily has its own Mafia, of which the character varies according to local tendencies and interest. In one place its energies are devoted to the conduct of the elections and the manipulation of the ballot-box; in another to directing, by means of a camorra, the sale of Church and Crown lands; in a third to the apportionment of contracts for the public works.|
If you’re wondering about the odd (for a New York City newspaper) references to St. Giles and Hounslow, it turns out the NY Times was reprinting an article that originally ran in the Edinburgh Review. You can see the complete article, The Mafia, as it originally appeared in the newspaper.
And that murder I mentioned? That was also written up in the the NY Times on October 22, 1888.
Turns out there’s an even earlier FirstMention, though it took a search on a double-f Maffia to find it in the September 24, 1874 New York Times.