In Irish Celtic mythology and lore birds were symbols of freedom and tran-scendence, having the power to soar up above the earth into the heavens, and return to bring messages from the gods. They thus symbolised spiritual messengers and mediators between earth-bound mortals and the heavenly world.

healing / protection / prophecy / vision / power
Although its reputation was sometimes dubious, the raven was considered an oracular bird, often representing the upsets and crises of life which were deemed necessary for anything new to be created. The raven is seen as a messenger between the two worlds – this and the next and symbolised the connection between this world and the Otherworld, and the raven was seen as a messenger between the two. The Irish Druids divined according to the flight and cries of birds, and in particular the raven and the crow, and saw them as birds of divination and prophecy and thus lodged raven and crow symbolism firmly in the folk imagination, and in Celtic mythology and lore.
The Celts celebrated New Year's Eve, "Samhain," on 31st October, a night of supernatural magic when the spirits of their ancestors appeared to feasting villagers. This festival survives as Halloween. Irish Celtic goddess Morrigan, as a raven, rules over Samhain, blessing those born at this time with vision and power. It was cautioned that great care should be taken when dealing with this important totem animal symbol of the celtic druids. This bird was also connected to celtic Bran the Blessed. In Welsh, "Bran" means "raven."
Celtic mythology and lore even today shows the association of the raven with prophecy and protection and is openly fostered in the heart of London (the Tower). In the tale of Celtic Bran the Blessed, the prophetic god-king Bran (which means ‘Raven’) asks that his head be cut off and buried on the White Mount in London, facing the direction of France. As long as his head remained buried there it would protect the kingdom. The Tower of London was later built on the site of the White Mount, and the magical protective power of the buried head was symbolised by the presence of ravens, which are kept at the Tower to the present day to fulfil Bran’s prophecy and ensure the safety of the realm.
Druid History---Celtic Symbols: Spirals---Celtic Ogham Alphabet
Celtic Symbols: Animals---Celtic Magic---Celtic Symbols: Cross