William Butler Ogden was a pioneer railroad magnate, one of the earliest founders and developers of the city of Chicago, and an important influence on U.S. westward expansion. His career as a businessman stretched from the streets of Chicago to the wilds of the Wisconsin lumber forests, from the iron mines of Pennsylvania to the financial capitals in New York and beyond. Jack Harpster’s The Railroad Tycoon Who Built Chicago: A Biography of William B. Ogden is the first chronicle of one of the most notable figures in nineteenth-century America. Harpster traces the life of Ogden from his early experiences as a boy and young businessman in upstate New York to his migration to Chicago, where he invested in land, canal construction, and steamboat companies. He became Chicago’s first mayor, built the city’s first railway system, and suffered through the Great Chicago Fire. His diverse business interests included real estate, land development, city planning, urban transportation, manufacturing, beer brewing, mining, and banking, to name a few. Harpster, however, does not simply focus on Ogden’s role as business mogul; he delves into the heart and soul of the man himself. The Railroad Tycoon Who Built Chicago is a meticulously researched and nuanced biography set against the backdrop of the historical and societal themes of the nineteenth century. It is a sweeping story about one man’s impact on the birth of commerce in America. Ogden’s private life proves to be as varied and interesting as his public persona, and Harpster weaves the two into a colorful tapestry of a life well and usefully lived.