Setting up Human on HorseBack Animation

I want to animate a person on horseback and the horse walking.

I am very very new to rigging and related stuff. I think I have to parent the pelvis of the character to one of the backbones of the Horse.

I have not found any tutorials on this, I have found some where it is a gameplay feature (Horse riding), I want this only as an animation, nothing more.

What should be the general workflow for something like this?