Hoodening

Hoodening is an ancient custom that involves people or practitioners to dress up in animal skins or to carry the heads of animals in a ritual or some form of dance or parade. This custom was recorded and condemned in England over a thousand years ago, which indicates that the origins of hoodening more than likely stretch back into the Heathen mists of time. It is recorded that the Archbishop Theodore is said to have condemned the practice of those 'whom on the calends of January clothe themselves in the skins of cattle and carry heads of animals', whilst it is also said that Saint Augustine condemned the 'filthy practice of dressing up like a horse or stag'. Giving strength to these quotes is other surviving evidence that shows that horses, cattle and stags were in some way venerated or used in religious ritual. It is well recorded that cattle and oxen were ritually sacrificed to Heathen gods in ancient England. So it could be possible that the skins of these sacrificed animals were worn during similar hoodening rituals. Horses were very much sacred in ancient times, this can be recorded as far back as fifth century England where, two brothers called Hengest (stallion) and Horsa (Horse) could originally have been worshipped as twin horse gods in a cult that was recorded as far back as the first century by the Roman historian Tacitus.
Whilst today there are, in some form, surviving examples of such hoodening customs, the most well known and popular is that of Abbots Bromley Horn Dance, which itself is said to have continued pretty much unbroken for many many centuries.

http://www.homestead.com/englishheathenism/folkcustoms.html