Josiah Warren (1798 - April 14, 1874) was an American reformer, inventor, musician, printer, typographer, author (True Civilization; Equitable Commerce; Manifesto, written at Robert Owen's community, New Harmony).

He was a co-founder, with Stephen Pearl Andrews (1812 - 1886), of Modern Times community. Warren is sometimes called "the first individualist anarchist in America".

From January, 1833, Warren published The Peaceful Revolutionist, arguably the first anarchist paper in the world. Philosopher John Stuart Mill, an admirer of Warren, in his Autobiography adopted Warren's phrase "Sovereignty of the Individual".

Warren was cited in the article on Anarchism by none other than Prince Peter Kropotkin in the famed 1910 edition of The Encyclopaedia Britannica. Others Kropotkin cites include Stephen Pearl Andrews, Lysander Spooner, Benjamin Tucker, Herbert Spencer, Pierre-Joseph Proudhon, August Spies, Albert Parsons.

Kropotkin adds: "anarchism is connected with all the intellectual movement of our own times. J.S. Mill's Liberty, [Herbert] Spencer's Individual versus the State, Marc Guyau's Morality without Obligation or Sanction, and Fouillée's La Morale, I'art et la religion, the works of Multatuli (E. Douwes Dekker), Richard Wagner's Art and Revolution, the works of Nietzsche, Emerson, W. Lloyd Garrison, Thoreau, Alexander Herzen, Edward Carpenter and so on; and in the domain of fiction, the dramas of Ibsen, the poetry of Walt Whitman, Tolstoy's War and Peace, Zola's Paris and Le Travail".