What is "robber baron"

n. 1 (context historical English) In Europe, an aristocrat who charged exorbitant fees or otherwise exacted money from people who journeyed across land or waterways which he controlled. 2 (context chiefly US idiomatic usually derogatory English) Especially in the 19th and early 20th centuries, a business tycoon who had great wealth and influence but whose methods were morally questionable and often unethical.

A robber baron or robber knight (German raubritter) was a feudal landowner that, seeking to alleviate their financial difficulties, recurred to banditry protected by his feud's legal status. It is a modern historiographical term based on historians' observations of the German nobility. This development is described to have occurred in the late Middle Ages and have been mainly a result of the natural economy displacement by the monetary economy.

Some robber barons violated the custom under which tolls were collected on the Rhine either by charging higher tolls than the standard or by operating without authority from the Holy Roman Emperor altogether. They also went outside that society's behavioral norms, since merchants were bound both by law and religious custom to charge a "just price" for their wares. During the period in the history of the Holy Roman Empire known as the Great Interregnum (1250–73), the number of tolling stations exploded in the absence of Imperial authority. They could resort into robbing ships of their cargoes, stealing entire ships or kidnapping.

The term Raubritter was coined by Friedrich Bottschalk in 1810.

"Robber baron" is a derogatory metaphor of social criticism originally applied to certain late 19th-century American businessmen who used unscrupulous methods to get rich.