Anon asked (PB some time ago) for information on Railroad Tycoons. Anon was looking for one person connected to all the RRs. Haven't found that person yet but here is some info to get started. Digging something else at the moment.
Ralph Budd - Great Northern Railroad 1919–1932
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=ralph_budd
Norris, Ernest E. - Southern Railway System 1937–1952
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=ernest_e_norris
Sloan, Matthew S. - Missouri-Kansas-Texas Lines 1933–1944
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=matthew_s_sloan
Spencer, Samuel - Southern Railway System 1894–1906
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=samuel_spencer
Willard, Daniel - Baltimore and Ohio Railroad 1910–1941
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=daniel_willard
Young, Robert R. - Chesapeake and Ohio Railway Company
https://www.hbs.edu/leadership/20th-century-leaders/Pages/details.aspx?profile=robert_r_young