Celtic religion was practised by ancient Celtic peoples of western Europe prior to Christianity.
Celtics believed in a number of different deities, and their religion was also animistic, believing in spirits existing in natural objects such as trees and rocks. Religious beliefs and practises of the Celts varied throughout the different Celtic lands, which included Ireland, Britain, Celtiberia, Gaul, areas along the Danube river, and Galatia; however there were commonalities shared by all.
Some Gods of the Celts were deities of major natural occurrences, such as the sun. The Celts did not worship the sun, but saw it as a symbol for that aspect of divinity. These deities were generally worshipped across the Celtic lands, however, they often went under different names. An example of this was the god Lugus, who appeared in later Irish mythology as Lugh, and in later Welsh mythology, where he appeared as Lleu Llaw Gyffes.
Another widespread pan-Celtic god was Taranis, a god of thunder, whose worship has been detected as having occurred in Gaul, Britain and Hispania. Other similar deities included Toutatis, a god of tribal protection in Gaul and Britain, Belenos, a god of healing, and Cernunnos, a horned figure found in Gaul.
There were also pan-Celtic goddesses. Examples of this include a mother goddess (such as Danu from Ireland and Dôn from Wales), a goddess of water (such as Sulis), and a goddess of horses (such as Epona in France, Macha in Ireland, and Rhiannon in Wales).
When the Romans conquered the Celtic lands of Gaul, Hispania and Britain, they equated the Celtic gods with their own deities. For instance, they claimed that the Gaulish Celtic god Belenos was the same as their own god Apollo, and that Lugus was the same as their own Mercury.