Germanic boar helmets or boar crested helmets are attested in archaeological finds from England, Denmark and Sweden, dating to Vendel and Anglo-Saxon periods, and Old English and Old Norse written sources. They consist of helmets decorated with either a boar crest or other boar imagery that was believed to offer protection in battle to the wearer. They have also been proposed to be a costume for the ritual transformation into a boar, similar to berserkers, and to be associated with Freyr.

The boar was an important symbol in prehistoric Europe, where, according to the archaeologist Jennifer Foster, it was "venerated, eulogised, hunted and eaten ... for millennia, until its virtual extinction in recent historical time." Anglo-Saxon and Vendel era boar symbols are preceded by a thousand years of similar iconography, coming after La Tène examples in the fourth century BCE, Gaulish specimens three centuries later, and Roman boars in the fourth century CE. The boar is said to have been sacred to a mother goddess figure among linguistically Celtic communities in Iron Age Europe, while the Roman historian Tacitus, writing around the first century CE, suggested that the Baltic Aesti wore boar symbols in battle to invoke her protection. Four legions, including the twentieth that was stationed in Britain, also adopted the boar as their emblem. The sole unequivocal depictions of boar-crested helmets outside of Germanic sources are on interior plate E of the Gundestrup cauldron, dating to the La Tène period or early Roman Iron Age, which is commonly believed to be Celtic in origin but also has elements suggesting Thracian origin.

Boars had a prominent role for the Germanic peoples and were closely associated with battle. The boar's snout formation was a wedge formation first attested in the 4th century CE, used by the Germanic peoples and named due to its appearance. The formation was also used in the medieval period, as attested in sources such as Knýtlinga saga and Ólafs saga Tryggvasonar. In Gesta Danorum, Book VII, the formation is taught by Odin to Harald Wartooth, who was named due to the tusks he grew to replace two of his teeth that fell out while he was young.

In mythological sources, the boar Saehrimnir is killed each day to feed the einherjar, while Gullinbursti and Hildisvíni are owned by the gods Freyr and Freyja respectively. Both Freyr and Freyja share names with swine, with boars referred to as Vaningi, a name for Freyr, and Freyja as Sýr (sow). In a ritual context, swine are often sacrificed and eaten during blóts (in particular the sonarblót), and are central in some forms of heitstrenging, where the boar is described as being holy. Scholars have proposed the sonarblót was devoted to Freyr, while in the U and H manuscripts of Hervarar saga ok Heiðreks, the link between the god and Heitstrenging is explicit. Guldgubbar finds include figures of swine and their ritual deposition has been linked with Vanir worship.

Boar symbolism and religious practice is closely associated with Sweden, a cultic centre for Freyr, and where it has been suggested to have been a totemic animal. Both the Swedish Yngling royal family and families of Icelandic settlers that can be traced back to Sweden are described as specifically worshiping Freyr and owning boars. A number of Germanic names feature as an element in names related to jǫfurr (derived from Proto-Germanic: *eburaR, wild boar) such as Jǫfurfǫst and Jǫfurbjǫrn, attested in Swedish runic inscriptions, and Eofor, a Geat in Beowulf. In later sources, jǫfurr the meaning of 'boar' and has been predominantly replaced by 'ruler' or 'prince'. This transition has been proposed due to the association between boar helmets and nobility.

Despite the numerous associations between boars and the Vanir, Freyr and Freyja, the boar also has symbolism in its own right and is not always linked with the gods.

Both boar-crested helmets and crest fragments dating to the Anglo-Saxon period have been discovered in England such as the Benty Grange helmet found in Derbyshire, dating to the 7th century CE. Boars also feature on the eyebrow terminals of the Sutton Hoo helmet which shares features both with other Anglo-Saxon and Vendel-era helmets, and has been suggested to have been made in Sweden. It has been proposed that a post-Roman introduction of a Germanic tradition from the European mainland, rather than the continuation of a tradition in Britain through 400 years of Roman rule, resulted in the return to prominence in the Anglo-Saxon period.

The Benty Grange boar has been suggested to have originally been fitted with boar bristles which would form an accentuated dorsal crest, a motif that has been suggested to point towards the animal's aggression and ferocity, consistent with martial associations. It has also been proposed that the golden decoration of the boar represents Freyr's boar Gullinbursti who has golden bristles, however there is no direct evidence that this story was known in England at the time of construction.