From Yahoo! Tech:
The date: May 3, 1978. The culprit: Gary Thuerk, a marketer for the old Digital Equipment Corporation. His crime: Sending a sales e-mail to 393 users on Arpanet (then a U.S. government computer network and the predecessor of today’s Internet). Little did Thuerk know that he’d just become the world’s first spammer.
That first piece of junk e-mail (which wasn’t called “spam” until about 15 years later) has been memorialized over at Brad Templeton’s Web site (Templeton is a Net pioneer, the creator of the legendary rec.humor.funny Usenet group, and chairman of the Eletronic Frontier Foundation), along with a thread of outraged replies.
Thuerk’s message was first greeted by a stern reprimand from one Major Raymond Czahor, chief administrator of Arpanet, followed by a long discussion thread as Arpanet usersâ€”many of whom were wary of censorship on their messaging networkâ€”mulled the impact of this first piece of junk e-mail:
“I don’t see any place for advertising on the ARPAnet,” user Mark Crispin wrote at the time. “Certainly not the bulk advertising of that DEC message. From the address list, it seems clear to me that the people it was sent to were the Californians listed in the last ARPAnet directory. This was a clear and flagrant abuse of the directory! I am not sure as to how far this should be carried though.”