Before the coming of Christianity, the various peoples of Europe (such as the Greeks and Romans and the Celtic, Germanic and Slavic tribes) practised their own indigenous religions. These religions were polytheistic, recognising many gods and goddesses as well as ancestral spirits and spirits of place. People interacted with their gods and spirits by making them offerings and requesting their help in exchange. Christianity took root in Rome when the Emperor Constantine converted in the year 312. Over the ensuing centuries the political power centre in Europe moved from the Roman Empire to the Roman Catholic Church and pagan societies converted to the new religion -sometimes voluntarily, often through coercion. By the year 1300, almost all of Europe was (at least nominally) Christian. Old gods had either been transformed into saints or declaimed as devils. Pagan practices were either absorbed into Catholicism or forbidden.

However, since Greek and Latin continued to be the languages of the educated throughout Europe up until modern times, interest in classical mythology remained strong. Greek and Roman gods were frequently depicted in the art of the Renaissance. In the romantic period of the 19th and early 20th centuries, nationalistic feelings led many Northern European countries to begin looking to their own native mythologies - hence the pagan themes to be found in the music of Wagner, the poetry of Tennyson, and pre-Raphaelite art. The Victorian period also brought about an interest in spiritualism and mysticism which continued into the early 20th century and resulted in groups like the Hermetic order of the Golden Dawn. All this set the stage for the advent of Neo-Paganism. The first Neo-Pagan traditions to appear in the 1950s and 60s were guided more by enthusiasm than scholarship and therefore bear little resemblance to ancient pagan religions. Wicca is often described as a religion for the 20th century. It was created in the 1950s by a retired British civil servant called Gerald Gardner, who drew upon such sources as Masonic rites, folklore, Catholic holidays, and medieval ceremonial magic.

Many off-shoots of Wicca soon sprang up, using the same basic ritual format but adding different emphasis. Because Wicca recognises a female deity, 'The Goddess', it gained popularity amongst feminists, and because The Goddess was often identified as 'Mother Earth', it gained popularity amongst environmentalists.

During the 1970s and 80s, it became increasingly clear in educated circles that most of the assumptions about ancient paganism that formed the basis of Wicca were misguided, especially the assumption that all pagan religious practices constituted 'witchcraft'. At the same time, with Western societies becoming increasingly multicultural, many people of European origin began taking an interest in their own cultural roots. It was in this environment that the ancient pagan religions of Europe began to be revived based on the latest scholarly evidence for their actual beliefs and practices. These traditions are known as 'reconstructed' pagan religions to distinguish them from modern pagan religions.

Reconstructed pagan religions are firmly based in the historical pre- Christian practices of a specific culture and adapted, where necessary, to modern times. Reconstructionists base their religious practices on those described in ancient literature, such as Ovid's Metamophoses or the Old Norse Sagas and Eddas. They look to the latest archaeological evidence for further clues. Where there is little or no historical information about a particular aspect of religion, they tend to seek divine guidance. Where aspects of the ancient religion clash with modern lifestyles, an attempt is made to find a substitute that is compatible with the symbolism and function of the original rite.

Reconstructed European religions include Hellenism (ancient Greek religion), the Religio Romana, Heathenry (ancient Germanic religion), Celtic Reconstructionism (not to be confused with Neo-Pagan Druidry!), Slavic Reconstructionism and others. All of these religions are polytheistic. They recognise a large number of gods, goddesses and other spiritual entities whom they see as distinct and real individuals. Rites take different forms depending on the religion, but all involve making offerings (usually of food or drink) to gods, ancestors and spirits. The calendar of seasonal festivals also varies widely and the number celebrated can range from only three in some forms of Heathenry to twenty-three in some forms of Hellenism. Practitioners of reconstructed pagan religions tend to meet in small groups of family or friends. Because they are few and far apart, and because they lack funding from any 'mother church', they have no public temples. Ceremonies may take place outdoors in holy spaces or in the homes of the celebrants.