Ancestor worship is a religious form of worship which emphasizes the influence of deceased relatives on the living. The veneration of ancestors is not a religion in and of itself, but a facet of religious expression which recognizes an element beyond human control. This form of worship is at the core of the Old Custom (Forn Siðr). Consequently, the old Norse religious custom specifically, and the even older Germanic customs more generally, were not the polytheistic traditions that monotheistic-based scholars suggest.
The basis of the Germanic veneration of ancestors seems to stem from two principle ideas: (1) that “those who have gone before” have a continual and beneficent interest in the affairs of the living; and (2) more widespread, uneasiness, fear of the dead, with practices to placate them. The later ideas more often serve as a form of dispensing emotions than of worship.