From my Song Page

"It seems probable that the Poor Old Horse is in origin the magic-endowed wild stallion of the pagan fertility rites in pre_Roman Britain. In later Christian adaptation he became a horse's skull, painted in garish colors and carried round from house to house begging alms at Christmastide. For this observance it was customary to procure the skull from a hunting stable after the horse's flesh had been eaten by the hounds." John Runge

From Cecil Sharp's 'Folk Songs of England', Poor Old Horse is a landlubber relative of the familiar sea shanty: Say, old man, your horse will die,   And I say so and I hope so,   And if he dies I'll sell his skin, Poor old horse.
There can be no doubt that the land-variant, which Sharp found as a part of the hobby-horse drama in Nottinghamshire, Derbyshire and Yorkshire, is older by far. The hobby horse, an important actor in British springtime ceremonies, is a fantastic and sometimes terrifying mask which covers the entire body of the dancer. The horse-dancer goes the round of the community, often on May Day, alternately dying and being revived by his companions, symbolizing the death of the old year, and of the fertility of the earth. These spring-time antics of the hobby-horse, which still amuse tourists in certain remote districts of western England, are a genuine survival of ancient pagan fertility rites. That a horse-mask dances in Britain on May Day is one more evidence of the importance of the horse-cult, widespread in all Europe thousands of years ago. Therefore, this charming little comic fragment, which   Sharp had taught to all the school children in Britain, is a gentle breath of a pagan fertility rite that once upon a time was a compound of magic, religion, comedy and sex.

Cheers, S. in Seattle