After Leonardo da Vinci, the first man to really think about and design flying machines, besides a few enthusiasts whose efforts made very little impact, was the Englishman, Sir George Cayley. Cayley designed a few gliders that achieved short manned flights (although he never piloted them himself). His notes and published works were a great aid to those who came after.
The first man to really get the art of flying "off the ground", so to speak, was the German engineer, Otto Lilienthal. He flew over 500 times in his unpowered gliders, published his findings widely, and was a tremendous source of inspiration and knowledge for the Wright Brothers who achieved a real airplane flight at Kitty Hawk in 1903.
After the Wrights, the Frenchman, Louis Bleriot invented the worlds first successful powered and controlled monoplane, and triumphantly displayed its ability to fly in Paris in 1909.
In 1915 a German engineer named Hugo Junkers built the Junker J1 the first all metal monoplane. The J1 also introduced the cantilevered monoplane wing needing no cables to hold its weight.
Charles Lindbergh pushed the new technology to new hieghts (quite literally) by pioneering high altitude flying to save fuel, and crossing the Atlantic in his biplane, the Spirit of St. Louis.
There are a suprisingly large number of "also rans" in early aviation, some of whose stories are at least as colorful and/or inspiring as those above, and about whom I may write future articles, so many interesting topics, and so little time . . .