These heads were defleshed by leaving them out for the ravens and other scavengers to eat, then kept in a place of honor inside the houses, or put into special niches cut into the doorframes of their houses.
In Celtic myth, heads were thought to be the seat of wisdom as well as the residence of the spirit. It is possible that an enemy's head was severed to keep that person's spirit from coming back either etherially or in a new body to bedevil the tribe again.
Some tribes kept only the brains, and glued these together with some form of mucelage. They would then display the most important of them to guests and tell how they had defeated this partucular enemy through a warrior's prowess or through trickery. Others kept the skulls.
The taking of heads is attested to in the Irish cycles. Cu Chulainn took his share of heads, and at the feast of Mac Da Tho's Pig, a severed head belinging to the brother of one of the contestants for the hero's portion, decided the matter.
The severed head as the seat of wisdom and possibly of protection is relayed in the story of Bran. Bran was killed in battle, but before he died, he instructed his men to take his head and bury it back in Britain so he could watch over the country.
His men did as they were bid and brought the head back to Britain. Bran's head kept them company, and twenty years became as one night so that the troop of them arrived back home two decades later than they had thought. They buried Bran's head somewhere near modern-day London, and he remains as a sentinel against invasions.
Modern-day Celts do not take heads or fight to the death for the hero's
portion. The practice of carving pumpkins or gourds for Hallowe'en
is believed by some to come from this practice, though.