If my (fading) memory serves me correctly, when hangliders/microlight aircraft first came into being, it was not a requisite to have a licence, the authorities being very brave and tried to let things run for a while to see how it worked out.
When hang-gliders (first powerless, then powered trikes) first came into being they simply didn't exist and kept "not existing" for a while, as far as the regulations were concerned. They weren't certified aircraft, so the applicable legislation did not apply to them, but there were as yet no sets of rules specific for "non-certified aircraft". This included of course the flight crew licensing aspects. This state of affairs didn't last very long in most European countries.
Ciao,
Dg8000