From 1870 to 1900, Louisville became a larger part of the American Industrial Revolution. The expansion of railroads was a key factor to becoming a center for industry, trade and commerce. Paul Jones Jr. helped the city become a world leader in bourbon production, and Louisville was the largest tobacco manufacturer due to successful brokers like Andrew Graham. John Leather's jean cloth facility was among the most productive in the world. The largest box factory also resided in the city, and Louisville became the banking capital of the South. Author Bryan S. Bush details those behind the massive industry in the City of Progress.