First freestyle competition, 1974 Canadian Open Frisbee Championships, Toronto Canada.
Ken Westerfield and Jim Kenner teamed up with Jeff Otis, event coordinator for the Canadian National Exhibition, to produce the Canadian Open Frisbee Championships. It was at this Tournament that Westerfield and Kenner introduced an event called Freestyle Frisbee and won it
This was the first pairs freestyle competition ever. This event is now a premiere event at disc tournaments world wide
The history of freestyle frisbee events and techniques are covered in the FPA Freestyle Players Association, also in several articles on Wikipedia.