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 Christianisation, trees continue to play a significant role in the folk beliefs of the Germanic peoples.
Terminology
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 , a masculine noun, developed Old Norse meaning 'temple, idol', Old English 'temple, idol', and Old High German meaning 'holy grove, holy stone'. According to philologist Vladimir Orel, the term was borrowed from the continental Celtic * or, alternately, the same non-Indo-European source as the Celtic source. A more general term for a sacred place was reflected in Old Norse vé.
The Proto-Germanic masculine noun , which developed into Old Frankish ('holy grove'), similarly either developed from, or is otherwise connected to, Gaulish , Latin and Old Irish 'holiness'.
Another Proto-Germanic masculine noun , has given rise to words with a variety of meanings in various Germanic languages, including Anglo-Saxon , 'meadow', Middle Low German , 'bush', and Old High German , , 'grove, copse, bush'; it is cognate with Latin , 'sacred grove'.
Scandinavian placenames occur with the name of a deity compounded with , 'grove', or , 'wood'.
Attestations and archaeological record
Sacred trees and groves are widely attested among the records of the ancient Germanic peoples. Some scholars hypothesize that they even predated the development of temples (according to Rudolf Simek, "there were sacred woods long before there were temples and altars").
In his Germania, Tacitus says that the Germanic peoples "consecrate woods and groves and they apply the name of gods to that mysterious presence which they see only with the eye of devotion", Tacitus describes the grove of the Semnones and refers to a castum nemus ('chaste grove') in which the image of the goddess Nerthus was hallowed, and other reports from the Roman period also refer to rites held by continental Germanic peoples in groves, including the sacrifices in forest clearings of survivors by the Cherusci after their victory at the Battle of the Teutoburg Forest, recounted by Tacitus in his Annals based on a report by Germanicus. Such groves were sometimes dedicated to a particular deity: in addition to the case of Nerthus, there was a silva Herculi sacra ('wood sacred to Hercules', an interpretatio romana) near the River Weser, and the Semnones reportedly held their rituals in honor of the regnator omnium deus ('god the ruler of all'). The scholar of Germanic religion Jan de Vries noted that placenames such as Frølund (Denmark), and Ullunda, Frösvi, and Mjärdevi (Sweden), in which the name of a deity is compounded with words meaning "grove" or "wood", suggest a continuation of the same practice, but are found almost exclusively in eastern Scandinavia; however, there is a Caill Tomair recorded near Dublin, an oak forest apparently sacred to Thor.
Reverence for individual trees among the Germanic peoples is a common theme in medieval Christian denunciations of backsliding into paganism. In some cases, such as Donar's Oak (according to legend, felled by Christian missionary Saint Boniface), these were associated with particular gods, and the association of individual trees with saints can be seen as a continuation of the tradition into modern times.
The Landnámabók, which describes the settlement of Iceland and dates from the 13th century, tells of a skáld by the name of Þórir snepill Ketilsson who, after his crew encountered and fended off raiding vikings, arrived in Iceland and founded a sacred grove there: ...Thorir took possession of all of the whole of Fnjoskadale, as far as Odeila. He made his home at Lund [Old Norse 'grove'], and held the grove sacred.