Lincoln Steffens, Ray Stannard Baker, and Ida M. Tarbell are considered to have been the first muckrakers, when they wrote articles on municipal government, labour, and trusts in the January 1903 issue of McClure's Magazine. Muckrakers were a group of writers, including the likes of Upton Sinclair, Lincoln Steffens, and Ida Tarbell, during the Progressive era who tried to expose the problems that existed in American society as a result of the rise of big business, urbanization, and immigration.