The Poetic Edda contains various references to Ragnarök:
In the Poetic Edda poem Völuspá, references to Ragnarök begin from stanza 40 until 58, with the rest of the poem describing the aftermath. In the poem, a völva (a female seer) recites information to Odin. In stanza 41, the völva says:

The völva then describes three roosters crowing: In stanza 42, the jötunn herdsman Eggthér sits on a mound and cheerfully plays his harp while the crimson rooster Fjalar (Old Norse "hider, deceiver" ) crows in the forest Gálgviðr. The golden rooster Gullinkambi crows to the Æsir in Valhalla, and the third, unnamed soot-red rooster crows in the halls of the underworld location of Hel in stanza 43.

After these stanzas, the völva further relates that the hound Garmr produces deep howls in front of the cave of Gnipahellir. Garmr's bindings break and he runs free. The völva describes the state of humanity:

The "sons of Mím" are described as being "at play," though this reference is not further explained in surviving sources. Heimdall raises the Gjallarhorn into the air and blows deeply into it, and Odin converses with Mím's head. The world tree Yggdrasil shudders and groans. The jötunn Hrym comes from the east, his shield before him. The Midgard serpent Jörmungandr furiously writhes, causing waves to crash. "The eagle shrieks, pale-beaked he tears the corpse," and the ship Naglfar breaks free thanks to the waves made by Jormungandr and sets sail from the east. The fire jötnar inhabitants of Muspelheim come forth.

The völva continues that Jötunheimr, the land of the jötnar, is aroar, and that the Æsir are in council. The dwarfs groan by their stone doors. Surtr advances from the south, his sword brighter than the sun. Rocky cliffs open and the jötnar women sink.

The gods then do battle with the invaders: Odin is swallowed whole and alive fighting the wolf Fenrir, causing his wife Frigg her second great sorrow (the first being the death of her son, the god Baldr). Odin's son Víðarr avenges his father by rending Fenrir's jaws apart and stabbing it in the heart with his spear, thus killing the wolf. The serpent Jörmungandr opens its gaping maw, yawning widely in the air, and is met in combat by Thor. Thor, also a son of Odin and described here as protector of the earth, furiously fights the serpent, defeating it, but Thor is only able to take nine steps afterwards before collapsing dead from the Serpent's venom. The god Freyr fights Surtr and loses. After this, people flee their homes, and the sun becomes black while the earth sinks into the sea, the stars vanish, steam rises, and flames touch the heavens.

The …

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Various objects have been identified as depicting events from Ragnarök.
Thorwald's Cross, a partially surviving runestone erected at Kirk Andreas on the Isle of Man, depicts a bearded human holding a spear downward at a wolf, his right foot in its mouth, while a large bird sits at his shoulder. Rundata dates it to 940, while Pluskowski dates it to the 11th century. This depiction has been interpreted as Odin, with a raven or eagle at his shoulder, being consumed by Fenrir at Ragnarök. On the other side of the stone is a depiction of a large cross and another image parallel to the Odin figure that has been described as Christ triumphing over Satan. These combined elements have led to the cross as being described as "syncretic art," a mixture of pagan and Christian beliefs.
The Gosforth Cross (920–950), in Cumbria, England, is a standing cross of a typical Anglo-Saxon form, carved on all sides of the long shaft, which is nearly square in section. Based on the mythological stories found in Old Norse texts written in Iceland in the twelfth and thirteenth centuries, it has been assumed that the figural carvings of the Gosforth Cross depict Norse mythological episodes connected to Ragnarök. Apart from panels of ornament, the scenes include a Christian crucifixion, and possibly another scene in Hell, but the other scenes are generally interpreted as narrative incidents from the Ragnarök story, even by a scholar as cautious of such interpretations as David M. Wilson. The Ragnarök battle itself may be depicted on the north side. The cross features various figures depicted in Borre style, including a man with a spear facing a monstrous head, with one foot thrust into the beast's forked tongue and on its lower jaw, and the other is against its upper jaw, a scene interpreted as Víðarr fighting Fenrir.
The 11th-century Ledberg stone in Sweden, similarly to Thorwald's Cross, is regarded as alluding to the final battle of Ragnarök through the stones images. The stone features a figure with his foot at the mouth of a four-legged beast, and this may also be a depiction of Odin being devoured by Fenrir at Ragnarök. Below the beast and the man is a depiction of a legless, helmeted man, with his arms in a prostrate position. The Younger Futhark inscription on the stone bears a commonly seen memorial dedication, but is followed by an encoded runic sequence that has been described as "mysterious," and "an interesting magic formula which is known from all over the ancient Norse world."
On the early 11th-century Skarpåker Stone, from Södermanland, Sweden, a father grieving his dead son used the same verse form, fornyrðislag, as in the Poetic Edda in the following engraving:

Jansson (1987) notes that at the time of the inscription, everyone who read the lines would have thought of Ragnarö…

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Rudolf Simek theorizes that the survival of Líf and Lífþrasir at the end of Ragnarök is "a case of reduplication of the anthropogeny, understandable from the cyclic nature of the Eddic eschatology." Simek says that Hoddmímis holt "should not be understood literally as a wood or even a forest in which the two keep themselves hidden, but rather as an alternative name for the world-tree Yggdrasill. Thus, the creation of mankind from tree trunks (Askr, Embla) is repeated after the Ragnarök as well." Simek says that in Germanic regions, the concept of mankind originating from trees is ancient, and additionally points out legendary parallels in a Bavarian legend of a shepherd who lives inside a tree, whose descendants repopulate the land after life there has been wiped out by plague (citing a retelling by F. R. Schröder). In addition, Simek points to an Old Norse parallel in the figure of Örvar-Oddr, "who is rejuvenated after living as a tree-man (Ǫrvar-Odds saga 24–27)."
Theories have been proposed about the relation between Ragnarök and the 9th-century Old High German epic poem Muspilli about the Christian Last Judgment, where the word Muspille appears, and the 9th-century Old Saxon epic poem Heliand about the life of Christ, where various other forms of the word appear. In both sources, the word is used to signify the end of the world through fire. The Christian thought of the Last Judgment as it is presented in the Book of Revelation is similar to the apocalyptic story of Ragnarök, which features imagery of a final cosmic conflict, devastation, and eventual renewal. Key elements, such as the role of a savior figure and the contrast between divine forces and evil, may mirror Christian theological concepts brought during the conversion of Scandinavia. Old Norse forms of the term also appear throughout accounts of Ragnarök, where the world is also consumed in flames, and, though various theories exist about the meaning and origins of the term, its etymology has not been solved.
Parallels have been pointed out between the Ragnarök of Norse religion and the beliefs of other related Indo-European peoples. Subsequently, theories have been put forth that Ragnarök represents a later evolution of a Proto-Indo-European belief along with other cultures descending from the Proto-Indo-Europeans. These parallels include comparisons of a cosmic winter motif between the Norse Fimbulwinter, the Iranian Bundahishn and Yima. Víðarr's stride has been compared to the Vedic god Vishnu in that both have a "cosmic stride" with a special shoe used to tear apart a beastly wolf. Larger patterns have also been drawn between "final battle" events in Indo-European cultures, including the occurrence of a blind or semi-blind figure in "final battle" themes, and figures appearing suddenly with surprising skills.

Similar Indo-European mythological elements are highlighted by comparisons between Ragnarök and Iranian prophetic tra…

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