Adapted from an article by Pia Guldager Bilde: "By Torch-light: The Cult in the Sanctuary".
So far we talked a bit about the Lake Nemi and it's surroundings. Now we shall look into the cult of the goddess that was worshipped ther: Diana Nemorensis.
Diana is traditionally described as the goddess of the hunt. And as such, there could hardly be a better place than Nemi, because the Alban hills would have been a paradise for hunters in ancient times. But this is only one of her aspects. It is always difficult to describe a deity with few words, because they have different description in different times and cultures, even if they have the same name. And goddesses with different names may be similar.
Thus at Nemi, we find votive gifts in bronze and terracotta showing Diana in a short chiton, a small cloak, boots and with a bow in her hands. This Diana is the gallant and chaste goddess and sister of Apollo, ie. identical to the greek Artemis.
But then we also find votive gifts in the form of parts of the body, particularly the hands, feet or eyes. But there are also replicas of the wombs and the penis, which shows that the desire for children was strong. The votives demonstrates that Diana had power over health and sickness. Wether medical healing was practised at Nemi is not known, but varoius doctor instruments are found. It is also possible that the bathing facilities at the Sanctuary in Nemi had a therapeutic purpose.
However, Diana's most common appelation is Trivia (sometimes she is also called Diana Triformis), which means the place where three roads meet, or more general, a cross road. At such liminal regions - meeting points between two worlds - dangerous forces are at work. It was particularly Hekate who reigned there, and it was important for travellers to offer correct sacrifices for her. Trivia also alludes to the three faces of Diana. Virgil Servius explains that she rules over three spheres: the underworld, the earth and heaven. This means that she has power over birth, life and death. Servius also says that the three faces of Diana represent the three faces of the moon, the waxing, the full and the waning. (Thus he describes Diana as a triple goddess or moon goddess).
It was in her aspect as Hekate, Goddess of the underworld that this dark goddess was worshipped. Literary sources tell about women, who wished her to answer their prayers, wandering from Aricia to the Sanctuary in the black night, carrying a torch, and with wreaths of flowers in their hair. (Sometimes the Goddess was called Diana Lucifera, and it is not difficult to find similarities with Lucina, Luna (Selene), and even the Sancta Lucia celebrations)
Her darker side also comes to the fore in the myth concerning the founding of the Sanctuary, according to which the original cult is an offshoot of the cult of the Taurian or Scythian Artemis, and Diana Nemorensis is sometimes called Scythian Diana. This cult-image demanded human blood, and any strangers who sailed past the point where the temple of Artemis was situated, were sacrified to her.
This myth may explain a bloody ritual of the Sanctuary, namely the succesion of its priesthood where the Priest-King, Rex Nemorensis had to fight a duel to the death with a challenger, who was a runaway slave, like himself. This duel may be a ritualisation of an ancient practise, where the worship of the goddess included human sacrifice, just like the worship of many other deities of the ancient world.
The universal character of Diana Nemorensis meant that she was venerated in the same sancturay together with the Egyptian goddess Isis with whose identity she became partly assimilated. Here we recognize the all-powerful Goddess whose origin is lost in the remotes stirrings of the religious consciousness of the Mediterranean lands. Linguistic evidence indicates that Diana was a very old Italic goddess, and historical evidence shows that she had a cult at Nemi as far back as the sixt century B.C.E. The Rex Nemorensis, indicates that the cult is in fact far older than that.