First spam ever

Wikipedia:

In the late 19th Century Western Union allowed telegraphic messages on its network to be sent to multiple destinations. The first recorded instance of a mass unsolicited commercial telegram is from May 1864. Up until the Great Depression wealthy North American residents would be deluged with nebulous investment offers. This problem never fully emerged in Europe to the degree that it did in the Americas, because telegraphy was regulated by national post offices in the European region.

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