Heard about this one few weeks ago on @crimsonclad's FullForce show. Why were we talking about Medieval MMA on a show about metal? Most probably because this is metal on few levels. And because that was one of the normal talks there :) If you have nothing to do you can check it out on MSPWaves or Palnet discord in about 4 hours.
Back to this craziness.
Yes it is official, they even have a International Medieval Combat Federation. In essence it is a Medieval fight tournament. They use rules of medieval tournaments, weapons made are reproductions based on the weapons of that period, but they had to be blunt, they are wearing full armor.
There are two types of tournaments. One on one in a ring that resembles the MMA rings.
And group fights with full craziness.
From what i managed to learn i think for some reason they split and now there are two big world tournaments. One is called Battle of nations
Second is by International Medieval Combat Federation.