19 robber barons who built and ruled America

America's tycoons in the 19th and early 20th centuries, pejoratively nicknamed "robber barons," built massive empires and accumulated unprecedented wealth.

Many of these men gained their vast fortunes either at the expense of their factory workers or by methods that were considered unscrupulous even back then - a time when insider trading wasn't yet outlawed. But some of them also gave away their fortunes to build universities, hospitals, libraries, and museums that still dot America today.

The debate over business ethics continues to this day. And so, a look at the ruthless business practices and accomplishments of 19 tycoons who built and ruled America.

Editor's note: This feature is inspired by an earlier version written by Gus Lubin, Michael Kelley, and Rob Wile.