While not modern MMA the Gracie brothers were doing their vale tudo fights before Bruce Lee was born. Though obviously they were mostly using the techniques tha

While not modern MMA the Gracie brothers were doing their vale tudo fights before Bruce Lee was born. Though obviously they were mostly using the techniques that today is called BJJ the fights themselves had almost no rules. This also meant no rounds or stand ups so if a BJJ fighter managed to pull a striker to ground the fights is effectively over. Problem back then was information. Pre internet and stuff happening really far away from each other (Brazil and Hong Kong/USA). UFC and the internet really helped to spread information on what actually works to a much wider audience (and from there to a group of practitioners) and thus sped up the development of the techniques a lot. UFC also made it possible to make a living from actually fighting instead of teaching others which is/was the “traditional” way of making money from martial arts which allows the fighters to fully concentrate on their own skills.