"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.
The term robber baron derives from the Raubritter (robber knights), the medieval German lords who charged nominally illegal tolls (unauthorized by the Holy Roman Emperor) on the primitive roads crossing their lands or larger tolls along the Rhine river — all without adding anything of value, but instead lining their pockets at the cost of the common good (rent seeking).
The metaphor appeared as early as February 9, 1859, when The New York Times used it to characterize the unethical business practices by Cornelius Vanderbilt. Historian T.J. Stiles says the metaphor, "conjures up visions of titanic monopolists who crushed competitors, rigged markets, and corrupted government. In their greed and power, legend has it, they held sway over a helpless democracy." Charles R. Geisst says, "in a Darwinist age, Vanderbilt developed a reputation as a plunderer who took no prisoners." Hal Bridges said that the term represented the idea that "business leaders in the United States from about 1865 to 1900 were, on the whole, a set of avaricious rascals who habitually cheated and robbed investors and consumers, corrupted government, fought ruthlessly among themselves, and in general carried on predatory activities comparable to those of the robber barons of medieval Europe."
The term combines the pejorative senses of criminal ("robber") and aristocrat ("barons" having no legitimate role in a republic). Hostile cartoonists might dress the offenders in royal garb to underscore the offense against democracy.
Historian John Tipple has examined the writings of the 50 most influential analysts who used the robber baron model in the 1865-1914 period. He argues:
American historian Matthew Josephson further popularized the term during the Great Depression in a 1934 book. Josephson alleged that, like the German princes, American big businessmen amassed huge fortunes immorally, unethically, and unjustly. The theme was popular during the 1930s amid public scorn for big business. Historian Steve Fraser says the mood was sharply hostile toward big business: