58 B.C. Julius Caesar said of Druidism:
It is believed that the doctrine of the Druids originated in Brittany, and was brought from that island to Gaul; even today, those who wish to study it in depth often go there to learn’ (Gaius Julius Caesar Gallic War).

Druids had divinatory practices based on their deep connection and communion with Nature. They received divine messages and lived in their forest.
The Druids were the only ones in their clan who could interpret Divine messages, and the only ones who could address their Divinities.
Their clan also included all their Ancestors, who guided those who lived.

Their divinatory aids were the shape of trees, their foliage, the movement of branches, and certain plants such as hou, mistletoe and elder. They also used animals and stones.

The oak, natural and supernatural element for the Duids, this tree which greatly appreciates the sun and which represented it in Celtic countries, king tree of the forest and axis tree of the world connecting Heaven to Earth, and man to the Divine .
Mistletoe is rare and grew on several of their trees, such as elm or beech, but because it grew on the sacred oak, mistletoe was considered divine essence by the Druids.

It also had this intrinsic spiritual component because it is a shrub that grows on its host tree but has no contact with the ground.
The oak is a symbol of the sun, and the berries of the mistletoe are white and shaped like full moons. Oak and mistletoe form the union of feminine and masculine, yin and yang and the harmony of Divine Nature.

Mistletoe is a perennial plant that does not wither. .

Mistletoe also grows in Australia, New Zealand, South Africa, South America and the magical thing is that all these mistletoe flower and ripen their berries simultaneously, although those in the hemisphere northern are in the winter period while the other mistletoes in the southern hemisphere are in the summer period. For all the mistletoe in the world, their flowering and maturation seem united by a common ancestral force of growth and life.

The Druids’ divinatory reveals were, among other things, the shape of the trees, their foliage, the movement of the branches, certain plants such as hou, mistletoe, and elderberry. They also used animals and stones.

To predict the future, and to know for example whether to give battle or not, the druids observed the berries on the holly branches, their number and growth.

During rituals to give their predictions and prophecies, they used mistletoe, interpreting the designs formed on the ground.
Druids also prophesied and made predictions during the mistletoe harvest.

The elderberry had a healing power like mistletoe but also a divinatory power of its own.
The Druids were also mediums using their elderwood flutes to communicate with their ancestors or receive divine messages, through messages, visions and flashes and practiced magic and rituals.

A druid was therefore a scholar, priest, sacrificer, philosopher, mathematician, jurist, orator, sorcerer, medium, healer, marriage counselor, political leader, teacher, jurisconsult, orator, astrologer, philosopher, mage and possessed a large number of filter recipes magical.
The Druid also had to know how to handle certain weapons (dagger, club, javelin, bow, spear, etc.), his shield and could wear his armor, all this even if he was exempt from military service.