Fly away

I used to be a pied piper - I led everyone on a merry dance. I was a Grand Old Duke - people followed me to the tops of tall hills and the bottoms of dark valleys. I kissed all the girls. I made a few of them cry. I sent them from me - "Fly away, Peter! Fly away Paul!" But, when I cried "Come back, Peter, come back, Paul!", no-one answered and no-one came.