Well kind of discovered. Salicin, the main component, is found in Willow Bark. The use of willow bark dates back to the time of Hippocrates. That’s 400 BC. I’m sure most of us know the Weeping Willow Tree. I sure climbed enough of then when I was a kid. There are beautiful trees.
It is reported that chewing the bark works better than Acetylsalicylic Acid. Imagine.