AN: This is mostly an idea outline so drop me a line if it should be continued. If you wish to write your own version using this idea or any idea in this outline, so long as you contact me first I most likely won't have any problems with that.
Harry Potter/Star Wars crossover
What if Obi-Wan Kenobi was the reincarnation of the Ancient Master Wizard Harry Potter? What if Obi-wan remembered his former life as Harry and how to use magic (without a wand) ? How would this knowledge of ancient magic affect Obi-Wan's life as a Jedi?
Magic was forgotten by almost all of the humans in the galaxy ages ago when the original human planet (Earth) was destroyed when its sun went supernova. The survivors with the ability to do magic never got training and when they meet with other species, the ability was declared the Force and never contested. What remaining references to magic were in children's books and even there it was being replaced by references to the force.
Once Obi-wan realized that there were no books on magic other than myths and legends he started to write down the knowledge as it came into his mind. He wrote in English, a language that no one else could read and all the knowledge in his mind was in English and behind shields very different from the ones taught in the temple.
Using his magic was dangerous because it worked best when emotions are used to strengthen the power behind it. To use the energy in front of other Jedi could lead to problems as emotions were considered the path to the dark side. Obi-wan had seen the dark side of humanity in his memories as Harry and was the only initiate who would survive outside the Temple alone before becoming Jedi Knights, or at least Padawans.