Things don't really change that much, do they?
16. Why Is It Called "Blackmail?"
The first blackmailers were Scottish landlords who exploited farmers by making them pay rent in livestock or services if they couldn’t pay in cash. The goods they had to hand over were usually worth more than the rent owned, and the landlords didn’t make change.
Around the same time, local chieftains started going after the same farmers with the kind of scheme the mafia usually refers to as "selling insurance." They made an offer the farmers couldn’t refuse: pay a fee for protection. If the farmers didn’t pay, then the chieftains would unfortunately be unable to prevent ruffians from destroying crops and sacking property.
The Scottish farmers called both nefarious deals "black" because they associated that color with evil, and because both payments were made in goods rather than silver coins (called "white money"). As for the "mail" part, it doesn’t refer to the postal system. That "mail" comes from the German word for "pouch." The "mail" in blackmail is related to the Old Norse word for "payment" or "agreement."
Neatorama’s note: The photo above is of Monty Python’s skit Blackmail [wiki], where "Michael Palin plays a smarmy television game show host who extorts money from his viewers by threatening to reveal embarrassing or illegal facts about them. One game is "Stop the film," where a scandalous film is played until a phone call is received, and the amount of money needed increases the longer the subject waits."
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