We've always thought that "techno" emerged during the mid-80s...but would you believe it if I told you that the first techno song was recorded in the '60s? If I clarified that Delia Derbyshire was the perpetrator, though, you'd probably realize that if anybody was going to invent and then dismiss a new electronic artform, it would be her.
It would seem that Derbyshire kept stacks of old reel-to-reel experiments in her attic, and after her death the BBC started going through and cataloging them. They found some truly amazing things, as described in this NoiseAddicts post.
Most interesting was a very capable techno song, recorded during the '60s and therefore without sequencers, keyboards, samplers, or even multi-track technology...I assume it was created using the traditional Radiophonic method: a bunch of reel-to-reel recorders all in a row, each playing a meticulously-constructed tape loop.
You can hear the mindblowing results here, including a brief dismissive prologue by Derbyshire herself.