Robber Barons

As the cartoon above suggests, all extremely wealthy men in the Gilded Age were not considered "Captains of Industry." Instead, they were termed "Robber Barons" because they earned their fortunes on the backs of their workers.

According to Boundless.com

The term "robber baron" was applied to powerful 19th century industrialists who were viewed as having used questionable practices to amass their wealth. On the other hand, "captains of industry" were business leaders whose means of amassing a personal fortune contributed positively to the country in some way.

The term derives from the medieval German lords who legally charged tolls on ships traversing the Rhine without adding anything of value. U.S. political and economic commentator Matthew Josephson popularized the term during the Great Depression in a 1934 book by the same title. He attributed the phrase to an 1880 anti-monopoly pamphlet about railroad magnates. Like the German antecedents, Josephson alleged that American big businessmen amassed huge fortunes immorally, unethically, and unjustly. The theme was popular during the Great Depression, a time of public scorn for the abuses of big business.

With respect to the image above:

This media file is in the public domain in the United States. This applies to U.S. works where the copyright has expired, often because its first publication occurred prior to January 1, 1923.

Source: Boundless. “Robber Barons and the Captains of Industry.” Boundless U.S. History. Boundless, 26 May. 2016. Retrieved 27 Sep. 2016 from https://www.boundless.com/u-s-history/textbooks/boundless-u-s-history-textbook/the-gilded-age-1870-1900-20/the-second-industrial-revolution-144/robber-barons-and-the-captains-of-industry-771-2148/