Holly bushes have been closely associated with Celtic mythology. The Holly King was said to rule from the summer until the winter solstice. At which time, the Oak King rose to power and reigned until the summer solstice when the Holly King took the throne again. Then the Oak King retired for his six-month reprieve until he battled the Holly King again.
Fun facts:
The holly bush is thought to symbolize the crown of thorns Jesus wore before He died on the cross. The red berries represent the blood He shed.
In pre-Victorian England, the young women slept with holly leaves under their pillows to dream about their future husbands while the young men carried the leaves and berries in their pockets, hoping to attract the young maidens.