The Fates are a common motif in European polytheism, most frequently represented as a trio of goddesses. The Fates shape the destiny of each human, often expressed in textile metaphors such as spinning fibers into yarn, or weaving threads on a loom. The trio are generally conceived of as sisters and are often given the names Clotho, Lachesis, and Atropos, which are the names of the Moirai, the version of the Fates who appear in Greek mythology. These divine figures are often artistically depicted as beautiful maidens with consideration to their serious responsibility: the life of mortals. Poets, on the other hand, typically express the Fates as ugly and unwavering, representing the gravity of their role within the mythological and human worlds.

The Moirai, meaning "allotted portion" or "share", separated each sister into a different role in order to handle the fates of humans. The Fates were expected to appear within three days of a mortal's birth. Clotho was the first of the three, known as "the spinner" because she wove the threads of human life while in the womb. This act is used to represent her divine duty, also incorporating pregnancies or birth when referring to her. The second Fate, Lachesis, is known as "the Allotter" or "the Receiver", given the fact that her responsibility includes determining how much mortal life is assigned to the soul of each individual. This, in turn, determines the number of tribulations that individual is predestined to face. The final Fate, Atropos, is known as the most stubborn sister of the three, given the nickname "the un-turnable" or "the Inevitable". Atropos is expected to cut off the thread of life, completing the cycle and determining when a human will die. She is typically seen hand in hand with death and the Underworld. Once Atropos cuts the thread, each soul is sent to the Underworld where they receive judgement and are sent to one of three options: Elysium, Tartarus, or the Fields of Asphodel.

Elysium is labeled a land for the blessed, whereas those who committed horrible deeds were sent to the deepest part of the underworld, Tartarus. The mortals who lived neither an objectively good or bad life were sent to the Fields of Asphodel.

The Fates have appeared in numerous cultures with similar tales. In Greek mythology, they appear as incarnations of destiny named the Moirai. The Roman counterparts of the Moirai are known as the Parcae. In Albanian folk beliefs the Ora and Fatí are three fate goddesses, the weavers of destiny, who control the order of the universe and enforce its laws. In Albanian tradition, Ora is also regarded as a type of personal fate goddess who belongs to a single individual. The trio of Fates also appears in Slavic culture as the Rozhanitsy, figures who foretell an individual's destiny. Similar to Greek mythology, the Fates are known as incarnations of destiny called Norns in Norse mythology. The biggest variant within these cultures remains in Baltic mythology, which characterizes the Deivės Valdytojos as seven sisters who weave pieces of clothing from the lives of humans.

The Fates are three Proto-Indo-European fate goddesses. Their names have not been reconstructed, but such a group is highly attested in descendant groups. Such goddesses spun the destinies of mankind.

Although such fate goddesses are not directly attested in the Indo-Aryan tradition, the Atharvaveda does contain an allusion comparing fate to a warp. Furthermore, the three Fates appear in nearly every other Indo-European mythology. The earliest attested set of fate goddesses are the Gulses in Hittite mythology, who were said to preside over the individual destinies of human beings. They often appear in mythical narratives alongside the goddesses Istustaya and Papaya, who, in a ritual text for the foundation of a new temple, are described sitting holding mirrors and spindles, spinning the king's thread of life.

In the Greek tradition, the Moirai ("Apportioners") are mentioned dispensing destiny in both the Iliad and the Odyssey, in which they are given the epithet Κλῶθες (Klothes, meaning "Spinners"). In Hesiod's Theogony, the Moirai are said to "give mortal men both good and ill" and their names are listed as Klotho ("Spinner"), Lachesis ("Apportioner"), and Atropos ("Inflexible"). Hesiod also describes the fates as being the daughters of the night. In his Republic, Plato records that Klotho sings of the past, Lachesis of the present, and Atropos of the future.

In Roman legend, the Parcae were three goddesses who presided over the births of children and whose names were Nona ("Ninth"), Decuma ("Tenth"), and Morta ("Death"). They too were said to spin destinies, although this may have been due to influence from Greek literature.