Sacred trees and groves in Germanic paganism and mythology

Trees hold a particular role in Germanic paganism and Germanic mythology, both as individuals (sacred trees) and in groups (sacred groves). The central role of trees in Germanic religion is noted in the earliest written reports about the Germanic peoples, with the Roman historian Tacitus stating that Germanic cult practices took place exclusively in groves rather than temples. Scholars consider that reverence for and rites performed at individual trees are derived from the mythological role of the world tree, Yggdrasil; onomastic and some historical evidence also connects individual deities to both groves and individual trees. After Christianization, trees continue to play a significant role in the folk beliefs of the Germanic peoples.

The pagan Germanic peoples referred to holy places by a variety of terms and many of these terms variously referred to stones, groves, and temple structures. From Proto-Germanic *xaruʒaz or *haruʒaz, a masculine noun, developed Old Norse hǫrgr meaning 'temple, idol', Old English hearg 'temple, idol', and Old High German harug meaning 'holy grove, holy stone'. According to philologist Vladimir Orel, the term was borrowed from the continental Celtic *karrikā or, alternately, the same non-Indo-European source as the Celtic source. A more general term for a sacred place was vé.

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