By the mid-1800s Buck Duke felt that a merger of all large-scale tobacco manufacturers would be a practical way of reducing selling and advertising costs as well as improving overall organization.  The four most important competitors of the Duke firm at that time were the Allen and Ginter Company of Richmond, the F. S. Kinney Company and the Goodwin Company both of New York, and William S. Kimball and Company of Rochester; these and the Duke company manufactured 90 percent of the nation's cigarettes in the 1880s.  After discussing the merger, and following a period of excessive spending on advertising, the large rival firms agreed that the Dukes' plan of merger was the most sensible proposal.  In 1890, the five principal companies united to form the American Tobacco Company.  This combination quickly became known as the "tobacco trust" because of its almost complete monopoly of the tobacco trade.

James B. Duke in 1890 controlled the largest tobacco industry in the world; the combined firms continued to grow in the next two decades.  However, by the turn of the century, anti-trust sentiment was increasing rapidly in the United States.  The prevailing feeling of the public that monopolies were harmful concentrations of power resulted in the dissolution of the American Tobacco Company by a ruling of the 

 United States Supreme Court in 1911.  Four major tobacco corporations were among those companies which emerged from the separation of the trust: a new American Tobacco Company, Liggett and Myers, P. Lorillard, and R. J. Reynolds.

Following the court action, Buck Duke carried on his tobacco business abroad and invested money in the development of hydroelectric power.  Later, Duke was to follow in the footsteps of his father and brother in distributing his fortune for the benefit of religious, educational, and medical institutions.  Washington and Benjamin had established a pattern of giving money to support the Methodist school, Trinity College, in Durham; James B. continued the tradition when, in 1924, the Duke Endowment was created for the benefit of his native region.  In addition to the establishment of Duke University, formerly Trinity College, the multi-million dollar indenture provided funds for educational institutions, orphanages, hospitals, and the Methodist church in the Carolinas.  As a result of the family's generous gifts, millions of people throughout the region have enjoyed a better quality of life.