As Naoko said Sailor Moon is based in the Greek and Roman Mythology

Selene/SailorMoon/Usagi (Greek Mythology)
Selene is know wearing robes, carrying a torch, wearing a half moon on her head and being riding a silver chariot drawn by two horses. Selene had many love affairs, the most popular with Endymion, the human Shepard.
Selene's parents are the Titan Hyperion and Theia, the sister of. Some sources report that she is the daughter of the Titan Pallas, Helios, or Zeus. Helius, who is the sun god as well as his father Helios, is the brother of Selene. Eos, the dawn, who is known for her numerous love affairs is the sister of Selene.
Here seduction with Endymion is the love affair that brings Selene the most fame. She fell in love with the Shepard, Endymion, and seduced him while he lies sleeping in a cave. Some sources say Endymion was a king or a hunter, rather than a Shepard. Her seduction of Endymion resulted in the birth of fifty daughters, one of which was Naxos. Since Selene was so deeply in love with Endymion she asked Zeus to allow him to decide his own fate. Zeus granted Selene's request, and Endymion chose never to grow old and to sleep eternally. However, Endymion's eternal sleep did not prevent him from Selene giving birth to his daughters. Endymion was visited by Selene every night and kissed by her rays of light.
Selene is a favourite of many poets, especially love poets. A moonlit night brings the feeling of romance. It is said that Selene's moon rays fall upon sleeping mortals, and her kisses fell upon her love, Endymion.

Endymion/ Tuxedo Kamen/ Mamoru (Greek Mythology)
Endymion was a handsome shepherd boy of Asia Minor, the mortal lover of the moon goddess Selene. Each night he was kissed to sleep by her. She begged Zeus to grant him eternal life so she might be able to embrace him forever. Zeus complied, putting Endymion into eternal sleep and each night Selene visits him on Mt. Latmus, near Milete, in Asia Minor. The ancient Greeks believed that his grave was situated on this mountain. Selene and Endymion have fifty daughters.

Pallas/ Sailor Pallas / PallaPalla
One of the Titans. Pallas is the son of Crius and Eurybia and husband of Stix. Pallas is the father of Zelus, Nike, Cratos and Bia. He is also occasionally considered the father of Eos.
Pallas is also an appellation of the goddess Athena (Pallas Athena) who, according to some accounts was the daughter of Pallas. In this version Pallas attempted to rape her and she killed him. From his skin she made the Aegis.

Ceres/Sailor Ceres/CereCere (Roman Mythology)
Ceres daughter of Saturn and Rhea. Wife-sister of Jupiter and mother of Prosperpina. Ceres is the goddess of grain, growing plants and the love that a mother bears for her child. In the Greek mythology she's know as Demeter.

Artemis (Greek Mythology)
The daughter of Leto and Zeus, and twin sister of Apollo. Artemis is the goddess of the wilderness, the hunt and wild animals, and fertility (she became a goddess of fertility and childbirth mainly in cities). She was often depicted with the crescent of the moon above her forehead and was sometimes identified with Selene (goddess of the moon). Her main vocation was to roam mountain forests and uncultivated land with her nymphs in attendance hunting for lions, panthers, hinds and stags. Contradictory to the later, she helped in protecting and seeing to their well-being, also their safety and reproduction. She was armed with a bow and arrows which were made by Hephaestus and the Cyclopes. In one legend, Artemis was born one day before her brother Apollo. Her mother gave birth to her on the island of Ortygia, then, almost immediately after her birth, she helped her mother to cross the straits over to Delos, where she then delivered Apollo. This was the beginning of her role as guardian of young children and patron of women in childbirth. Being a goddess of contradictions, she was the protector of women in labour, but it was said that the arrows of Artemis brought them sudden death while giving birth. As was her brother, Apollo, Artemis was a divinity of healing, but also brought and spread diseases such as leprosy, rabies and even gout.

Diana (Roman Mythology)
Diana is the mother of wild animals and forests, and a moon goddess. Oak groves are especially sacred to her. She is praised for her strength, athletic grace, beauty and her hunting skills. With two other deities she made up a trinity: Egeria the water nymph, her servant and assistant midwife; and Virbius, the woodland god. She’s also known in the Greek mythology as Artemis.

Luna (Roman Mythology)
The personified goddess of the moon. Later she is identified with Diana and Hecate. Her temple, on the Aventine Hill, was erected in the 6th century BCE but was destroyed by the great fire under Nero's regime. She is equivalent to the Greek Selene.

Juno/Sailor Juno/JunJun (Roman Mythology)
Juno was the Roman equivalent of the Greek goddess Hera and was considered the Roman supreme goddess, married to the ruling god, Jupiter. She is believed to watch and protect all women and was called by the Romans "the one who makes the child see the light of day". Every year, on the first of March, women hold a festival in honour of Juno called the Matronalia. To this day, many people consider the month of June, which is named after the goddess who is the patroness of marriage, to be the most favourable time to marry. Juno's own warlike aspect is apparent in her attire. She often appears armed and wearing a goatskin cloak, which was the garment favoured by Roman soldiers on campaign. In Rome she was worshipped on the Capital hill along with Jupiter and Minerva, goddess of wisdom and the arts. In the Greek she know as Hera.

Jupiter/Sailor Jupiter/Makoto (Roman Mythology)
Jupiter was the Roman sky god, the equivalent of the Greek god Zeus. The cult of the Jupiter Optimus Maximus ("the best and greatest") began under the Etrucan kings, who were expelled from Rome around 507 BC. At first, Jupiter was associated with the elements, especially storms, and lightning, but he later became the protector of the Roman people and was their powerful ally in war. The games held in the Circus in Rome were dedicated to him. In the Greek mythology is Zeus.

Mars/Sailor Mars/Rei (Roman Mythology)
Mars was the son of Juno and a magical flower and initially was the Roman god of fertility and vegetation but later became associated with battle. As the god of spring, when his major festivals were held, he presided over agriculture in general. In his warlike aspect, Mars was offered sacrifices before combat and was said to appear on the battlefield accompanied by Bellona, a warrior goddess variously identified as his wife, sister or daughter. Mars unlike his Greek counterpart, Ares, was more widely worshipped than any of the other Roman gods, probably because his sons Romulus and Remus were said to have founded Rome. As the consort of Rhea Sylvia and father of Romulus and Remus, Mars was considered the father of the Roman people. He is know, in the Greek mythology as Ares.

Mercury/Sailor Mercury/Amy (Roman Mythology)
Mercury was the Roman messenger god, and was also the deity who watched over trade and commerce, as his name suggests. He was associated with peace and prosperity. He was apparently imported from Greece around the fifth century BC. Mercury is usually depicted in the same way as his Greelk counterpart Hermes, with a winged hat and staff. He was, in the Greek mythology Hermes.

Neptune/Sailor Neptune/Michuru (Roman Mytology)
Neptune was an ancient Italian water god who the Romans identified with Poseidon. Compared to Poseidon, however, Neptune plays a minor role in Roman mythology.

Saturn/Sailor Saturn/Hotaru (Roman Mythology)
Saturn was an ancient Italian corn god, the Roman equivalent of the Greek god Cronos, though he had more in common with goddess Demeter. He was believed to have ruled the earth during a lost Golden Age. His festival, the Saturnalia, was celebrated in Rome over seven days and was held at the end of December.

Venus/Sailor Venus/Minako (Roman Mythology)
Venus was the Roman equivalent of Aphrodite, the Greek love goddess. Venus was the daughter of Jupiter and Dione, although sometimes portayed as being created by Uranus from the foam of the sea at the moment of his death. As the goddess of love, she is the "queen of pleasure" and mother of the Roman people. She was married to Vulcan, the lame god of the forge, and mother of Cupid, Hymen, Priapus and Aeneas. It was Venus who recovered her son Aeneas'spear during his fight with the Italian champion Tumus, thus saving his life. Venus is also associated with her lover, Mars the god of war. Considered a nature goddess, associated with the arrival of spring. Venus is the bringer of joy to gods and humans.

Vesta/Sailor VesVes/VesVes (Roman Mythology)
Vesta was the Roman equivalent of the Greek goddess Hesta, who was the goddess of the hearth. Vesta, however, was worshipped both as the guardian of the domestic hearth and also as the personification of the ceremonial flame. Ceremonies in her honour were conducted by the vestal virgins, who were young girls from noble families who took vows of chastity for the thirty years during which they served her. Vesta's chief festival, the Vestalia, was held on 7 June. Shes know in the Greek Mythology as Hestia.

The Mythology of some magical Items

The Holy Grail
Popular etymology used to explain the word as meaning the real blood of Christ, sang-real, or the wine used in the Last Supper. Tradition has it that Joseph of Arimathea preserved part of this wine-blood in the Saint, or Holy Grail. - To see more information about the holy Grail click here.