This is tricky one, because while the Wright brothers worked out how to actually control flight, and stay air born, someone with any kind large-surface lifting wings could get picked up and quickly dropped back down by a stiff breeze...that could have happened many times. However, a good candidate for first getting into a successful liftoff and short flight would be Otto Lilienthal, who managed to do short flights off of hillsides in his gliders, in 1891 managing to get around 30 meters. Despite not having warpable wings or ailerons, in photos you can see that his gliders somewhat resemble modern hang gliders, gained some stability because the weight of the pilot hanging below the wings tended to keep them horizontal. He was working to refine this on his last gliders, as well as trying other wing controls, but crashed and died of injuries before he could pursue it further.
He was very focused on imitating birds, and so when he attempted powered flight, he tried to do it by making flapping wings. Unfortunately it did not work well.