heres my two cents:

when this universe formed , gasses massed together and they began to have centralized gravity.

there began movement of these masses toward each other due to their gravitational pulls on each other , they approached each other and rotation began as they passed each other and through each other and some were accelerated in different or opposite rotations.

there were collisions upon collisions that caused rotation.

I doubt that a single galaxy exist that has no rotation.

if there did exist one the stars in that galaxy had no outward force that could hold them in any type of orbit , and they went in and this would have resulted in a black hole without a galaxy.

so to give a short answer to your question.

Gravity caused rotation.












3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.