"For 18 days in the summer of 1872, Patrick S. Gilmore, an Irish-born impresario, led the largest concert in history.
Some 20,000 singers and 2,000 musicians from around the world descended on Boston to participate in the World Peace Jubilee and International Music Festival, which ran from Bunker Hill Day to the Fourth of July, 1872. They performed in various ensembles and also en masse, to convey the joy, solace and inspiration that music brings, and to express a profound relief, even if temporary, that there was peace in the world."
An interesting feature from Michael Quinlin in the current Irish America Magazine.