I'm linking to a four part series produced by the History Channel called The Men Who Built America. The series focuses on John D. Rockefeller, Cornelius Vanderbilt, Andrew Carnegie, Henry Ford and J.P. Morgan, and how their business empires revolutionized modern society and also made them powerfully rich.
If you want to know the problems Theodore Roosevelt faced as the President in those days this is a much needed set of programs. Episode 4 is an absolute must! In episode 4 we see how "Rockefeller, Carnegie and Morgan team up to help elect William McKinley to the U.S. presidency by paying for his 1896 campaign, to avoid a possible attack on monopolies. However, fate intervenes when McKinley is suddenly assassinated, and vice president Theodore Roosevelt assumes the presidency and promptly begins dissolving monopolies and trusts in America." This series can also be found on Netflix and perhaps other such sites.