There are few reports of Baltic tribes, the ancestors of modern Latvians, and their mythology until Christianization in the 13th century. Since Christianization, there have been several reports related to local mythology including chronicles, travel reports, visitation records, Jesuit reports and other accounts of pagan practices. These reports are considered secondary sources by researchers because since the authors were not Latvian, they did not speak the local languages and often were biased. These materials are sometimes imprecise and contain errors, fabrications, and distortions stemming from a Christian world view. Despite this, they can often be verified using information from folklore. Most folklore materials have been collected since the mid-19th century.
In the 18th and 19th centuries, it was assumed that Baltic tribes were originally one nation and thus had the same deities. Early authors trying to reconstruct a Latvian pantheon using data from neighboring regions. This trend was later also adapted by Latvian national romanticists. After the abolition of serfdom, a new national identity was forming and authors sought to prove that Baltic cultural traditions were as deep as those of other nations. It was hoped that a grand epic could be constructed using pieces preserved in folklore. It was also thought that the ancient religion, forgotten during 700 years of oppression, could be reconstructed. However folklore sources proved insufficient for the task. Some attempted to reconstruct pantheons to be as impressive as in Greek mythology, which led to some deities being simply invented. Besides the assumption that deities of other Baltic peoples must be Latvian as well but were simply lost over time, many new deities were modeled after Greek and Roman deities. An example of the trend is the epic poem Lāčplēsis by Andrejs Pumpurs, which features a pantheon of Latvian and Prussian gods and some the author has invented himself. Similarly, works of Juris Alunāns and poet Miķelis Krogzemis feature pantheons of invented deities.
At the same time some pagan rites were still practiced. And, as Christianity was seen as alien, attempts were made to recreate the ancient religion. The most successful of the neopagan movements was Dievturi, established in late 1920s, which claims that ancient Latvians were monotheistic and the various mythological beings are all aspects of one God. While the notion of needing to remove alien influences to reconstruct Latvian traditions was preserved into later times, the attempts to create an Olympus-like pantheon of pseudo-gods eventually stopped as national romanticism was replaced by realism and came to be criticized in the first half of 20th century. It was also suspected that some of the folklore materials might have been falsified. The research of this time is characterised not only by skepticism, but also with attempts to seek foreign influences.
After the Second World War, under Soviet occupation, research of mythology and especially religious concepts was banned in Latvia. Similarly, members of neopagan groups were persecuted as paganism was considered chauvinistic. Despite this, research was continued by Latvians in exile, who focused on the mythology of folk songs. The songs were already seen as the best source for mythology research during the interwar period. The reason was that since the need to preserve poetic metre and melody limited possible changes, it was thought that ancient notions were better preserved in them than in other genres of folklore. Accordingly, folk songs were the only source for research for long time. This approach has been criticized by modern researchers who have proposed that themes mentioned in other genres, such as fairy tales, legends, and records of folk beliefs and magic practices, might compliment folk songs as each genre contains different themes and might provide only partial insight into mythology.
Although research in Latvia could only restart in the 1980s, the 1970s saw the emergence of a folklore movement with members which could be described as neopagans. These groups were pantheistic, less uniform, less dogmatic, interested in protection of nature and cultural heritage, and more open to the influence of traditions from neighboring nations. Later, marginal movements have explored spirituality in both local traditions and religious and spiritual practices of the world, such as Eastern religions. For example, Pokaiņi forest was announced to be an ancient sacral site by one of these groups in the late 1990s, and it attracts thousands of visitors each season. Dievturi, which resumed operating in Latvia just before restoration of independence in 1990, is the only officially recognized pagan religion and had around 600 followers As of 2001[update]. Given the decreasing influence of the movement, its name is sometimes applied in a broader sense to any modern practice related to folklore.
There are various reconstructions of Latvian mythical space, but most researchers agree on the meaning of certain features related to the sky. The sky itself is identified as Debeskalns (which means "Sky Mountain"). The sky is also referred to as Mountain of Pebbles, Silver Mountain or Ice Mountain, with the adjectives probably referring to stars or snow. It has also been suggested that Dievs (God) is also a symbol of the sky because the etymology of his name seems to be related to sky. Dievs is considered to be the supreme deity. Other related deities include the goddess of the sun, Saule, who ensured the fertility of the earth and was the guardian of the unlucky, especially for orphans and young shepherds. Her path leads her across the mountain of sky to the sea, which is sometimes interpreted as a symbolic representation of the sky or cosmic ocean. The sea and other bodies of water, including rivers, especially Daugava, seem to mark the boundary between worlds of the living and the dead. In Latvian, the word for "the world" is derived from the word for "the sun" and these worlds are referred to as "this sun" and "that sun". Therefore it seems that Saule is also closely related to the concept of death. She apparently carries the souls of the dead across the sea to the world of the dead. Her daily movement can thus be related to the cycle of human life with her being reborn every day.
On the path of the sun, in or by the water, often on an island or rock in middle of the seas, is the Austras koks (tree of dawn) thought to represent world tree or axis mundi, it is usually described as a tree, but can also be variety of other plants or even objects. Nobody has ever seen the tree, although folklore purports that many have searched all their lives. Still it has been suggested that its natural counterpart might be the polar star  or the Milky Way. It has also been proposed it might be symbol of a year. The tree is related to celestial wedding mythos in which sun or her daughter is courted by Dieva dēli (sons of god), Auseklis (Venus) or Pērkons (Thunder).
Also, as in Latvian the word for daughter (meita) also stands for maiden, it is uncertain who exactly is getting married. However this does not affect how mythical events transpire. The male deities spy on the solar deity at the world tree, prepare a bath for her, tease her and so on. Eventually she is abducted and wed (it has been suggested Saule’s husband is moon god Mēness). This angers Pērkons, who strikes the world tree, so weeping Saule has to pick up its bits for three years and then reassemble them, finishing with the very tip on the fourth year.
The world of the dead is called Aizsaule or Viņsaule. It is related to various mother deities (or perhaps one referred to by several names) - Zemes māte (mother of Earth), Veļu māte (Mother of wraiths), Kapu māte ("Grave mother"), and Smilšu māte – (Mother of Sand). Also related is a deity later identified with the Christian devil. All pagan deities were referred to as "devils" by some Christian sources, thus it is possible that this image is merger of several deities, first of all chtonic gods, and folklore does indeed refer to there being several devils, though occasionally there is one main entity identified. In Latvian fairy tales and legends the Devil is hardly ever evil. Rather he is physically strong, but somewhat lazy and easily fooled by Dievs (God) and humans alike. He also is said to have taken part in the creation of world and living things. His realm, unlike the Christian Hell, is depicted as similar to the world of living. Its entrances are located in forests, swamps, rivers, graveyards, caves, under rocks and in the sea. The devil steals people away to take them to his world. In this he is similar to other spirits who kill people, including the dead who were believed to sometimes come back to claim a life of a person they knew in their lifetime. The dead called Veļi (also Iļģi, Dieviņi, Pauri) were considered to be visiting their old homes during autumn from Miķeļi (September 29) to Mārtiņi (November 10). A Jesuit report from the end of 16th century suggests that historically a funeral procession was led by a person waving the axe to protect the deceased from other souls coming to him too fast. The deceased was buried with items of trade to be able to secure livelihood in the afterlife. Bread and beer was also given. In autumn the souls were invited back home for a feast. The house would be clean and table with foods set. At beginning of the feast an elder would invite the souls by calling the names of all the dead who once lived in the house the living could remember. He would then give a speech scolding them for not having protected the house well enough, ask them to do better next year and then invite them to eat. After the meal was done the souls would be chased out and house would be carefully cleaned to ensure no one had stayed behind and the dirt would be thrown in water. The dead could also be invited to chaste themselves in the bathhouse. The food could also be brought to the graveyard or left in the bathhouse, barn or granary. In that case it would be checked next morning to see if the dead had touched it, to figure out if they were benevolent to the living. In this case a candle would be lit so the dead could see the food. In some regions pails of milk and water along with a clean towel would also be left so the dead could wash themselves. Those who did not honour the dead were said to have a poor harvest. In modern Latvia a form of ancestor worship has been preserved in celebrating the Remembrance day of the dead in late November and in graveyard celebrations which are held in late summer.
The Latvian beliefs on evil spirits and sorcerers likely are a direct product of witch hunts in 16th and 17th centuries, though some elements may be a demonization of earlier beliefs. Accordingly, it was believed that sorcerers were servants of the devil. Called burvji, burtnieki (wizards) or raganas (witches) these might in reality have been folk medicine practitioners.
Laumas and spīganas, terms speculated to originally refer to different notions, were also used to refer to witches in some areas. With the help of the devil they could turn into various beings or have evil spirits serve them. It was suggested that spirits of the dead might serve the devil or may be used by him to appear to humans and to turn sorcerers. Thus the demons could variously be thought to be independent spirits or spirits of sorcerers flying around. It was thought that souls of sorcerers leave their bodies, which become dead and can then be permanently killed by turning it, as the soul then does not know how to return into the body.
There are also reports of werewolves (vilkači, vilkati)—humans who could turn into wolves. The turning usually didn't involve the help of the devil, but rather a ritual, which often necessitated undressing. The werewolf would leave his or her clothing and would be unable to turn back if somebody touched the clothes. There are conflicting reports on what forces they serve. According to one view, they serve the devil and guard entrances to hell during meetings of devils and sorcerers. They steal meat. However they are also reported to be "dogs of god" who fight sorcerers trying to steal flowers of grains, thus ensuring good harvest.
The witches are often reported to steal milk either by themselves or by employing toads and snakes, believed to be capable of sucking it from a cow’s udder and then regurgitating it on command.
Another spirit, sometimes said to be a sorcerer’s spirit but often a spirit in a sorcerer’s service was pūķis (dragon) – a fiery being who would steal grain and other riches and bring them to its owner. It would be red when "empty" and blue when "full" of riches. He would be kept in a separate room that would be kept very clean, where nobody could enter without the owner's permission. Pūķis would be fed the first bit of every meal. If pūķis felt that he was not revered enough he would turn on the owner and burn the house down.
A demon, sometimes related to sorcerers but usually said to be the soul of a child condemned to haunt until the time he or she ought to have died, is Lietuvēns, who tortures people, cattle, and horses during the night and who is associated with sleep paralysis.
Similarly, it is sometimes reported that Vadātājs is a ghost, sometimes of a prematurely deceased person and sometimes seeking to kill a person in way similar to his own death. Often, however, vadātājs is a devil himself. This demon attacks travelers, making them confused and unable to find their way. Often its aim seems to be to lead people to the nearest body of water, where they would drown.
The most important goddess of fate is Laima (Goddess of luck). She lives on Earth and is closely involved in human life. Her basic function is related to childbirth and deciding a child's fate. Traditionally women would give birth in bathhouses. The path leading to a bathhouse would be cleansed so Laima could easily make her way to help in the birthing process. The woman would be ritually cleansed and would offer prayers and give ritual offerings to Laima. After a successful birth, married women would feast, with Laima being reserved a place of honour in the bathhouse as sign of gratitude. She would also determine a person's fate – a decision even she herself could not alter afterwards. She was expected to help in other important aspects of life as well and cared for well being of the people in general. Unmarried girls would pray to her to give them good husbands and happy marriage. She also ensured fertility of fields and animals (horses in particular) to some extent. Another two goddesses with similar function are Kārta and Dēkla. Goddess Māra also has several functions in common with Laima. Although this view has been criticized, many researchers agree that Māra is synonymous with Saint Mary. It has been suggested that Mary took over some functions of earlier deities, including Laima. However, Māra was used to refer to Saint Mary, who was also called upon during childbirth and to help with number of ailments by either her modern Latvian name Marija or number of Christian euphemisms. All these were also used as euphemisms to refer to uterus in folk magic. The opposing view, based on comparative linguistics linking her with wide range of other Indoeuropean deities, is that she was important pre-Christian chthonic deity that both gives and takes life.
Ensuring fertility was an important function that was assigned to number of spirits and deities. Ensuring good harvest was primary function of Jumis. It was thought that he lives in the fields, therefore last of the crop would be left on field for Jumis to live in. This belief was basis of ritual catching of Jumis performed on Miķeļi, which usually was the last day of harvest. This seems to have involved singing songs as last of the grain was reaped asking Jumis to run to wherever crop was stored. Last bit of crop would be searched for Jumis and then tied into knot. Another related practice was to make wreaths of grain cereals, that would be kept until next year when seeds from them would be sown first. It was usually attempted to place Jumis stalks in these wreaths. In this sense Jumis is symbolized by stalks with two ears. Any fruit or flower showing such abnormal duplication was called Jumis. It was believed that eating Jumis would cause woman or female animal to give birth to twins. Ensuring wellbeing of livestock was, however, function of other gods. Ūsiņš who was associated with Jurģi celebration and thus somewhat merged with Saint George. He was worshiped mainly as guardian of horses. It is also thought he might have been god of bees and god of light. Main protector of cows seems to have been Māra. She is also known as lopu Marija (Mary of livestock), Lopu māte (Mother of livestock) and Piena māte (Mother of milk). Her function was to ensure cows give milk. Therefore she is also often mentioned in connection with water, rivers and sea as water symbolized milk, while clay symbolized butter. Historical sources also mention that Latvian pagans would venerate snakes (likely grass snakes) and toads as „milk mother” and feed them with milk.
There may have been a number of other spirits and deities venerated by Latvians. There is, for example, wide range of deities referred to as ”mother” – their number is variously estimated to be anywhere from 50 to 115. The reasons for such unclarity are that sometimes authenticity of certain "mothers” is questioned, there may be differences between regions in what deities are worshiped and also many of these are synonymous titles of a single deity. Mother and other kinship terms can be used merely to signify age and also to show respect (when referring to older people). While most female spirits are called "mothers”. Male spirits would be called "father” (tēvs) or "master” (kungs) or "god” (dievs, dieviņš) or "spirit” (gars, gariņš). Historical sources report that there was a belief that spirits live in the ground. There also are Mājas gari (house spirits) or Mājas kungs (master of house), who lived and were worshiped at homes. These sometimes were sacred animals. They were often fed first bit of every food. Spirits and deities were also worshiped in designated places, which could be visited only at certain times of year. It was believed that visiting them at other times or defiling, even unknowingly, such site in any way would bring great misfortune to guilty party - blindness or death are common examples. There were also animals, some known as dieva sunīšī (dogs of god), killing whom would bring misfortune, these include stoats, wolf, frogs, ladybirds etc. Sometimes, however, it was believed that killing would not bring misfortune, but if animal would get away it would take a horrific revenge. This mostly refers to snakes. Wolves, snakes were also not to be mentioned by name. There are similar beliefs of not mentioning the devil or plague. The reason for this taboo is belief that the being, harmful to humans, would come as called. Similarly whistling in certain places would invite devil, while singing would invite god. Therefore large variety of euphemisms were used instead, including comparisons, human names and other anthropomorphic terms – e.g. snakes were likened to ropes or called brides, while wolf was named Juris or Ansis or referred to as man (also brother or friend) of the forest.
- Kursīte, Janīna (2005). "Baltic Religion: History of study". In Jones, Lindsay. Encyclopedia of Religion 2 (2nd ed.). Thomson Gale. pp. 767–771.
- Ķencis, Toms (2011). "The Latvian Mythological space in scholarly Time" (PDF). Archaeologia Baltica (Klaipėda: Klaipėda University Press) (15): 144. Retrieved 21 August 2012.
- Rozenbergs, Jānis (1997). "Pārdomas par tematu "Garlībs Merķelis un latviešu folklora"". Latvijas Zinātņu Akadēmijas Vēstis (in Latvian) (Rīga: Latvijas Zinātņu Akadēmija) 51 (1./2.(588./589.)): 1–8.
- Muktupāvels, Valdis (2005). "Baltic religion: New religious movements". In Jones, Lindsay. Encyclopedia of Religion 2 (2nd ed.). Thomson Gale. pp. 762–767.
- Bērziņš, L. (1939), P. Šmits kā latviešu tautas dziesmu pētnieks, Filologu biedrības raksti XIX, Rīga
- Biezais, Haralds; Ankrava, Sigma (2005). "Baltic Religion:Overview". In Jones, Lindsay. Encyclopedia of Religion 2 (2nd ed.). Thomson Gale. pp. 756–761.
- Vīķe-Freiberga, Vaira (2005). "Saule". In Jones, Lindsay. Encyclopedia of Religion 12 (2nd ed.). Thomson Gale. pp. 8131–8135.
- Pundure, Irena (2011). "A solar calendar from Latvian dainas" (PDF). Archaeologia Baltica (Klaipėda: Klaipėda University Press) (10): 39. Retrieved 21 August 2012.
- Muktupāvela, Rūta (2005). "Ancestors: Baltic cult of ancestors". In Jones, Lindsay. Encyclopedia of Religion 1 (2nd ed.). Thomson Gale. pp. 327–331.
- Straubergs, Kārlis (1941). Latviešu buramie vārdi (in Latvian) II. Rīga: Latviešu folkloras krātuve.
- P. Šmits. "Latviešu tautas ticējumi". Artificial Intelligence Laboratory (in Latvian). Institute of Mathematics and Computer Science University of Latvia. Retrieved 21 February 2013.
- Biezais, Haralds (2005). "Laima". In Jones, Lindsay. Encyclopedia of Religion 8 (2nd ed.). Thomson Gale. pp. 5285–5286.
- Straubergs, Kārlis (1939). Latviešu buramie vārdi (in Latvian) I. Rīga: Latviešu folkloras krātuve.
- Kursīte, Janīna (2005). "Māra". In Jones, Lindsay. Encyclopedia of Religion 8 (2nd ed.). Thomson Gale. pp. 5691–5694.
- "Miķeļi (Apjumības)" (in Latvian). Retrieved 14 April 2014.
- "Jurģi (Ūsiņi)" (in Latvian). Retrieved 14 April 2014.
- "Mātes" (in Latvian). Retrieved 14 April 2014.
- "Mājas kungs" (in Latvian). Retrieved 14 April 2014.
- Latvian folklore/mythology (in Latvian)
- Latvian folk beliefs (in Latvian)
- Latvian fairy tales and legends (in Latvian)
- Latvian folk songs (in Latvian)
- Latvian pagan deities, festivals, design elements and folk costumes
- article "How to Kill a Dragon in Latvian": Indo-European poetry in the Latvian folk songs