Why do people kiss under the mistletoe?

The mistletoe has a muderous past in Norse legend

If someone is standing under the mistletoe, they may be kissed by someone else according to custom (Getty)

A sprig of mistletoe tied over the Christmas party dance floor or hanging in a doorway is generally taken as an excuse for people to pucker up.

But where does the custom come from?

It is mistletoe's properties that enable it to stay green in the winter, even when the tree has lost its leaves, that led both the Celts and Norse peoples to form myths about its special properties.

One tale from Norse legends, which were told by pre-Christian Scandinavian people in the fifth and sixth centuries, explains its association with love.

The youthful god Balder was the son of powerful sorceress Frigga and her husband, Odin, chief of gods.

Vintage engraving from 1882 of the Goddess Frigg amd her maidens. Frigg (Frigga) is a major goddess in Norse paganism. She is said to be the wife of Odin, and is the 'foremost among the goddesses' and the queen of Asgard (Getty)

Though adored by almost everything on earth, Balder began to have terrible premonitions of his impending death.

His mother, Frigga, in an effort to soothe his fears, asked "every creature which lives on or in the earth" to swear never to harm him - and as a result, the gods would throw things at Balder to show how invincible he now was.

But Loki, the disloyal trickster of the gods, knew that one living thing did not live on or in the earth - mistletoe, which lived entirely off the branch of a tree.

Detail from the Skogchurch Tapestry depicting the Norse gods Odin, Thor and Freyr. Sweden, 12th century. (Getty)

He made an arrow of mistletoe, shot it at Balder, and killed him.

Frigga was so distraught that her tears turned to white berries, coating the plant and symbolising her love for him.

Legend is divided as to whether she then forgave the mistletoe and said it should be a symbol of love and peace, or whether this then brought Balder back to life, showing the power of love.

Either way, this particular Norse legend is often given as the reason for mistletoe's special significance in bringing two people together.