The Ludlow Strike and Massacre in Colorado
Rockefeller was an underwriter of a loan, which allowed him and his son John Jr. to gain controlling interests in affiliations of the Colorado Fuel and Iron Company. In 1913 and 1914, labor fights among coal minors, labor organizers, and corporate interests led to extreme violence, which resulted in the deaths of women and children in the mining camps.
The Rockefellers were not personally involved in any of the violence or in hiring anyone who was. In fact, the Rockefeller Foundation underwent relief efforts in the aftermath. Still, public opinion and an outraged press (usually outrageously inaccurate) vilified Rockefeller and his reputation once again.