If we trace origins of anarchism in the United States, then probably Henry David Thoreau is the closest you can come to an early American anarchist. You do not really encounter anarchism until after the Civil War, when you have European anarchists, especially German anarchists, coming to the United States. They actually begin to organize. The first time that anarchism has an organized force and becomes publicly known in the United States is in Chicago at the time of Haymarket Affair.