Medieval improvisation

A really nice improvisation can be done in a simple way by using what we can call a "medieval style".

Ok, medieval is inappropriate as name, anyway the following improvisation sounds "medieval" (just as a pentatonic improvisation on the piano sounds "chineese"...):

so to have a nice "medieval" sound just reach out the keyboard and:
1) choose a scale
2) with your left hand play perfect fifths on that scale using mostly nearby tones (avoid diminshed fifths!!!). Use I - II - III - I, or I - VII - VI - I, ...
3) with the left hand make a "medieval" melody by sticking to the scale, using triplets and avoid big leaps. It is really useful to think to something medieval (a square in a town, a knight, a sword, ...) to make a medieval melody!!!
4) after some bars suddenly change scale/mode, starting from scratch with another scale, different from the beginning (use a far scale, at least "3 alterations away", like C to Eb)
5) repeat this changing of scales until you go back to the original scale and you complete the improvisation.

Note: if played on the organ it is nice to try some "distorsion", this means having expecially on the left hand some mutations (like XII) or a soft reed (cromohorne for example).

Experment and... Have Fun!