William Coleman, educated in public schools in Fond du Lac County, began his career as a house painter in Milwaukee. He became an active member of the Brotherhood of Painters, Decorators and Paperhangers Union of America and later served as a union organizer for the Painters' Union, Milwaukee Federated Trades Council, and Wisconsin State Federation of Labor. Coleman held leadership positions on the executive boards of the Council and the Federation. He ran for various political offices, including State Representative and Common Council, and was a Wisconsin delegate at the Socialist National Convention. Coleman's career highlights his commitment to labor rights and workers' unions, advocating for fair wages and improved conditions for laborers.

William Coleman's political identity is marked by his unwavering commitment to labor rights and union advocacy, yet his strategic alliances reveal a nuanced approach. His legislative efforts often bridged ideological divides to protect regional industrial interests, showcasing a calculated pragmatism. Coleman's rhetorical style consistently emphasized the plight of laborers, yet his surprising willingness to collaborate with opposing factions hints at a broader, less rigid ideology.