Dating back to the feudal period of medieval Europe, the derogatory term "robber baron" was applied to some of America's most notorious industrialists and financiers during the late 19th century.

Widely regarded as ruthless, unscrupulous, and entirely consumed by insatiable greed, these mercenary individuals were the original "fat cats," engaging in everything from shameless bribery and corruption to worker exploitation and manipulation of the stock market.

Read on to discover the 10 most notable examples, including a few who have perhaps been unfairly labeled with the term...

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