The sky often has important religious significance. Many religions, both polytheistic and monotheistic, have deities associated with the sky.
The daytime sky deities are typically distinct from the nighttime ones. Stith Thompson's Motif-Index of Folk-Literature reflects this by separating the category of "Sky-god" (A210) from that of "Star-god" (A250). In mythology, nighttime gods are usually known as night deities and gods of stars simply as star gods. Both of these categories are included here since they relate to the sky. Luminary deities are included as well since the sun and moon are located in the sky. Some religions may also have a deity or personification of the day, distinct from the god of the day lit sky, to complement the deity or personification of the night.
Daytime gods and nighttime gods are frequently deities of an "upper world" or "celestial world" opposed to the earth and a "netherworld" (gods of the underworld are sometimes called "chthonic" deities). Within Greek mythology, Uranus was the primordial sky god, who was ultimately succeeded by Zeus, who ruled the celestial realm atop Mount Olympus. In contrast to the celestial Olympians was the chthonic deity Hades, who ruled the underworld, and Poseidon, who ruled the sea.
Any masculine sky god is often also king of the gods, taking the position of patriarch within a pantheon. Such king gods are collectively categorized as "sky father" deities, with a polarity between sky and earth often being expressed by pairing a "sky father" god with an "earth mother" goddess (pairings of a sky mother with an earth father are less frequent). A main sky goddess is often the queen of the gods and may be an air/sky goddess in her own right, though she usually has other functions as well with "sky" not being her main. In antiquity, several sky goddesses in ancient Egypt, Mesopotamia, and the Near East were called Queen of Heaven.
Gods may rule the sky as a pair (for example, ancient Semitic supreme god El and the fertility goddess Asherah whom he was most likely paired with). The following is a list of sky deities in various polytheistic traditions arranged mostly by language family, which is typically a better indicator of relatedness than geography.
African
Central African
Khonvoum, Mbuti supreme creator god and sky father
Nzambi Mpungu, Bakongo creator, sky and sun god
Nzambici, Bakongo sky, moon and earth goddess
East African
Mulungu, Nyamwezi creator and sky god
Waaq creator and sky god.
Ancient Egypt
Achamán, Guanche creator and sky god
Amun, Ancient Egyptian god of creation and the wind
Anhur, Ancient Egyptian originally a foreign war god
Hathor, Ancient Egyptian originally a sky goddess
Horus, Ancient Egyptian god of the sun, sky, kings, and war
Khonsu, Ancient Egyptian moon god
Mehet-Weret, Ancient Egyptian goddess of the sky
Nut, Ancient Egyptian goddess of the sky
Ra, Ancient Egyptian god of the sun that ruled the sky, earth and underworld
Shu, Ancient Egyptian god of the air
Thoth, Ancient Egyptian original moon god
Southern African
Umvelinqangi, Zulu sky god
Utixo, Khoikhoi sky god
Xamaba, Heikum creator and sky god
West African
Denka, Dinka god of sky, rain and fertility
Nyame, Akan supreme deity, god of the sky
Olorun, Yoruba supreme deity, god of the sky and heaven
Osalobua, Benin supreme creator god and sky father
Shango, Yoruba sky father and thunder god
Wulbari, Guang sky god
European
Proto-Indo-European
Dyeus, the chief sky father of the Proto-Indo-European religion
Hausos, dawn goddess and daughter of Dyeus
Menot, moon god
Seul, sun goddess
Albanian
Zojz, god of the sky
Baltic
Auštaras, the god of the northeast wind
Dievs, the god of the day-lit sky and the chief god in Latvian mythology
Vejopatis, the god of the wind who guards the divine realm of Dausos
Celtic
Latobius, sky and mountain god equated with the Greek gods Zeus and Ares
Nuada, god of the sky, wind, and war
Sulis, goddess of the hot springs at Bath; probably originally the pan-Celtic sun goddess
Ambisagrus, Cisalpine god of rain, sky and hail equated to the Roman god Jupiter
English
Nuit, goddess of "Infinite Space and Infinite Stars" in Thelema
Germanic
Dagr, personification of day
Eostre, spring and fertility goddess; originally the Germanic dawn goddess
Mēnô, the moon
Nótt, personification of night
Sōwilō, the sun
Teiwaz, early Germanic sky god, also the god of law, justice, and the thing (assembly)
Greek
Aether, primeval god of the upper air
Apollo, god of the sun, archery, prophecy, medicine, plagues...
Astraeus, dusk god
Eos, dawn goddess
Helios, personification of the sun
Hemera, primordial goddess of day
Hera, goddess of the air, marriage, women, women's fertility, childbirth, heirs, kings, and empires
Iris, goddess of the rainbow and messenger of Hera
Nephele, cloud nymph in Hera's likeness
Nyx, primordial goddess of night
Selene, personification of the moon
Uranus, primeval god of the sky
Zeus, king of the gods, ruler of Mount Olympus, god of the sky, weather, law, order, and civilization
Messapian
Zis, god of the sky
Roman
Aurora, dawn goddess
Caelus, personification of the sky, equivalent to the Greek Uranus
Juno, goddess of the sky, queen of the gods, and Jupiter's wife, equivalent to the Greek Hera
Jupiter, king of heaven and god of the sky and weather, equivalent to the Greek Zeus
Luna, moon goddess
Nox, Roman version of Nyx, night goddess and mother of Discordia
Sol, sun god
Summanus, god of nocturnal thunder/lightning
Slavic
Dazhbog (or Svarog), god of the Sun
Khors, god of the Moon
Stribog, god of the winds, sky, and air
Perun, god of the thunderstorms, lightning and sky.
Triglav, a triple god whose three heads represent sky, earth, and underworld
Zorya, goddess of dawn
Thracian and Phrygian
Sabazios, sky father
Asian
Western Asian
Asherah, sky goddess and consort of El; after the rise of Yahweh, she may have become Yahweh's consort before she was demonized and the Israelite religion became monotheistic
Baalshamin, "Lord of the Heavens" (c.f. Armenian Barsamin)
El (god), original sky god and sky father of the Semitic speakers (replaced by Yahweh among Israelites)
Yahweh, Levantine sky god of the Midianites, Israelites and other ethnic groups in the region
Iranian
Asmān, god of sky
Māh, god of the moon
Ohrmazd, sky father, the Great God
Tīštar, god of Sirius star and Rainfall.
Xwarxšēd, god of the sun
Uša, goddess of dawn
Central Asian
Turkic and Mongolic
Tengri, god of the sky
Ülgen
Kayra
Hindu
Aditi, celestial mother of the gods
Chandra, god of the moon
Dyaus Pita, sky father
Indra, king of the gods, associated with weather
Ratri, goddess of night
Saranyu, goddess of clouds
Surya, god of the sun
Ushas, goddess of dawn
Varuna, a sky god
Eastern Asian
Vietnamese
Ông Trời, sky god in Vietnamese indigenous religion
Ông Tử Vi, king of the stars
Mẫu Cửu Trùng Thiên, she is the daughter of Ông Trời, the sister of the Mẫu Thượng Thiên, Mặt Trời, Mặt Trăng and also a goddess who rules the sky
Mẫu Thượng Thiên, she is the daughter of Ông Trời and also one of the rulers of the sky
Pháp Vân, cloud goddess
Thần Mặt Trời, goddess of the sun, daughter of Ông Trời
Thần Mặt Trăng, goddess of the moon, daughter of Ông Trời
Hằng Nga, the goddess who lives on the moon with uncle Cuội and Moon Rabbit
Thai
Phaya Thaen (Thai: พญาแถน,) the sky personified with a rank equivalent to marquess (Thai Phraya,) the protagonist in a Rocket Festival