There are literary sources that tell us how Heathenry was practised before the advent of Christianity. The main such sources include medieval Icelandic Eddas and Sagas, Anglo-Saxon poetry, the works of the 8th century English monk Saint Bede, and the Germania by the Roman historian Tacitus.
Although most of these were written in Christian times, they record the religious beliefs and practices of a culture that existed before Christianity came to Northern Europe. Archaeological evidence continues to be discovered which supports this picture of Heathen religion obtained from such classical and medieval literature.
Alongside these historical sources, modern Heathens experience their own, personal, understanding of their religion as lived today, and their own relationship with their gods.