Irish and Italian immigrants were vocal at the turn of the century. Vaudeville comic Walter Kelly received “a letter threatening his life if he did not immediately cut out several Italian stories in his act,” and an Irish betterment organization called the Clan na Gael pelted comedians with eggs for perceived slights against the Irish.
A newspaper editorial in Kansas feared this would inspire other groups to do the same: “If the well-known and almost indispensable Irish policeman is to be abolished from the stage by decree of the Clan-na-gael, what is to hinder the ‘Afro-American’ societies from following suit and threatening dire consequences on the heads of players who represent the stage type of negro?”
That’s precisely what happened. African Americans, Native Americans and American Jews all staged protests in the early 20th century. In 1903, the Topeka Capital predicted the death of comedy: “The final upshot [of protest is] to strip comedy of its most engaging and popular features. If the raid should extend to all sorts of people caricatured in the theater and in print, then good-bye to comedy.”