The People of the Abyss (1903) is a book by Jack London about life in the East End of London in 1902. He wrote this first-hand account after living in the East End (including the Whitechapel District) for several weeks, sometimes staying in workhouses or sleeping on the streets. In his attempt to understand the working-class of this deprived area of London the author stayed as a lodger with a poor family. The conditions he experienced and wrote about were the same as those endured by an estimated 500,000 of the contemporary London poor. London also used the expression "the people of the abyss" in his later dystopian novel The Iron Heel (1907).
When London wrote The People of the Abyss, the phrase "the Abyss," with its hellish connotation, was in wide use to refer to the life of the urban poor. H. G. Wells's popular 1901 book, Anticipations, uses the expression in this sense some twenty-five times, and uses the phrase "the People of the Abyss" eight times. One writer, analyzing The Iron Heel, refers to "the People of the Abyss" as "H. G. Wells' phrase."
George Orwell was inspired by The People of the Abyss, which he read in his teens, and in the 1930s he began disguising himself as a derelict and made tramping expeditions into the poor section of London himself, in emulation of Jack London. The influence of The People of the Abyss can be seen in Down and Out in Paris and London and The Road to Wigan Pier.
The British newspaper journalist and editor Bertram Fletcher Robinson wrote a review of The People of the Abyss for the London Daily Express newspaper. In this piece, Fletcher Robinson states that it would be "difficult to find a more depressing volume."