Neptune: The Evolving Roman God Of Fresh Water, The Sea and Horses

The ancient Romans believed that Neptune was the god of the sea. Although he is most commonly compared to the Greek god Poseidon, this had not always been the case. Originally, Neptune was a god of fresh water, and was only associated with Poseidon at a later date. Thanks to Neptune’s connection with Poseidon, there are many Roman myths in which the latter is substituted with the former.

Although many similarities can be drawn between Neptune and Poseidon, differences can also be seen. For instance, in ancient times, Neptune did not achieve the same kind of cult status enjoyed by his Greek counterpart. In modern times, however, Neptune’s legacy can be felt more strongly than Poseidon’s.

How Neptune Got His Name And His Early Origins

Neptune’s name is believed to be derived from the Indo-European word for “moist.” This word is also the basis for the Latin word nebulo, meaning “fog, mist, or cloud.” Neptune was originally a god of the ancient Italians. At that time, he was worshipped as a minor god who was in charge of fresh water and irrigation. Interestingly, the ancient Italians did not have a god of the sea.

Nevertheless, they did believe that there was a god who ruled over the enormous river believed to encompass the world. This was Oceanus, who was viewed as the opposite of Neptune. Another god, the Etruscan Nethun, was once thought to have made huge contributions towards the Italians’ development of Neptune. Nethun was believed to have jurisdiction over wells, and his power was extended later on to all bodies of water. In more recent times, however, scholars are of the opinion that the worship of Neptune preceded that of Nethun. Therefore, it is thought that Nethun’s development owed a great deal to Neptune, rather than the other way around.

A late 2nd century AD Roman mosaic entitled the “Triumph of Neptune,” from La Chebba, Tunisia. (Bardo National Museum / CC BY 2.0)

A late 2 nd century AD Roman mosaic entitled the “Triumph of Neptune,” from La Chebba, Tunisia. (Bardo National Museum / CC BY 2.0 )

How Neptune Went From Water God To Sea God

Neptune initially had nothing to do with the sea. As a matter of fact, when the Romans defeated their enemies at sea, they attributed their victory to Fortuna, rather than a sea god like Poseidon.

We know, however, that Neptune was officially connected with the Greek Poseidon as early as 399 BC. In that year, an interpretation of the Sibylline Books ordered a lectisternium, a ceremonial meal, in order to win the favor of the gods, and Neptune was one of the deities invited. The other gods honored with this ceremonial meal were Apollo, Latona, Hercules, Diana, and Mercury.

Based on this event, it may be said that Neptune was one of the earliest Roman deities to have been identified with a Greek deity. Since Poseidon was a major god in the Greek pantheon, Neptune’s association with him boosted his cult status immensely. Thus, Neptune was transformed from a minor god in charge of fresh waters to a major god who ruled the seas.

It is not known exactly what myths Neptune featured in before his association with Poseidon, if any. Once the link between the two gods was made, however, Neptune could conveniently be substituted for Poseidon in the existing myths. For instance, there is the well-known Greek myth of the Titanomachy, in which Zeus and his siblings seize power by overthrowing their father, Cronus, and the Titans. In the Roman version of the myth, Zeus is replaced by Jupiter, Cronus by Saturn, and Poseidon by Neptune. Therefore, Neptune was now the brother of Jupiter, and one of the most powerful gods in the Roman pantheon.

Following the defeat of Saturn, Jupiter divided the world between himself, Neptune, and Pluto (Hades to the Greeks). Whilst Jupiter became the god of the sky, and Hades ruler of the underworld, the seas became Neptune’s domain. As the god of the sea, Neptune is usually portrayed with a trident, his weapon and symbol of power. This is an apt object, as it is a three-pronged spear used by fishermen. In addition, the god is often depicted with fish, and sometimes other sea creatures as well.

Neptune and his wife Salacia at a fountain near the Hofburg Palace in Vienna, Austria. (neurobite / Adobe Stock)

Neptune and his wife Salacia at a fountain near the Hofburg Palace in Vienna, Austria. (neurobite / Adobe Stock )

For the Romans, Neptune’s official wife was an obscure goddess called Salacia, who is speculated to have been an ancient Italian deity of salt water. This goddess has been identified with the Greek Amphitrite, the eldest of the 50 Nereids. According to one version of the myth about Amphitrite’s marriage to Poseidon, the god of the sea desired to marry the Nereid. Amphitrite, however, preferred to keep her virginity, and therefore fled to Atlas. Poseidon sent his subjects to seek Amphitrite, including a dolphin called Delphin. The sea creature eventually found Amphitrite, persuaded her to marry Poseidon, and took charge of the wedding.

For his contributions, Delphin was later placed in the sky as a constellation. Like his brother Jupiter, however, the god of the sea was also involved in many extramarital affairs, which resulted in numerous offspring. In Greek mythology, the heroes Theseus, Bellerophon, and Orion are all said to be the sons of Poseidon. It would be reasonable to expect that the Romans also regarded Neptune as the father of these heroes. Incidentally, Pegasus, Bellerophon’s winged horse, was also an offspring of Poseidon / Neptune.

In most accounts, Neptune and Salacia had three children, Triton, Rhodos, and Benthesikyme. The merman Triton is arguably the most famous of Neptune and Salacia’s three children, and there are various myths about him. In one of these myths, which relates to Jason and the Argonauts, Triton is depicted a god residing in Lake Tritonis. This is a large body of fresh water in North Africa mentioned in classical mythology, though its exact location is unclear. In any event, Jason and the Argonauts got lost in the middle of a desert, and it was Triton who helped them find their way back from the lake to the sea.

The god Triton as a fishlike Centaur blowing a bugle. Triton was the ancient Roman god messenger of the deep. He was the son of Neptune and Salacia. (dikson / Adobe Stock)

The god Triton as a fishlike Centaur blowing a bugle. Triton was the ancient Roman god messenger of the deep. He was the son of Neptune and Salacia. (dikson / Adobe Stock )

Triton appears quite commonly in ancient art, in which he is depicted with the upper body of a man, and the lower body of a fish. Like his father Neptune, Triton also wields the trident. The god’s most recognizable attribute, however, is the conch shell, which he uses as a trumpet to herald Neptune’s arrival. In some versions of the myth, Triton’s conch shell trumpet has the power to calm or raise the waves. One popular Athenian black figure vase painting depicts Triton wrestling Heracles.

Neptune’s Rule Over Fresh Water Stayed And Horses Were Added

Although Neptune became the Roman god of the sea, his roots as a god responsible for fresh water was not entirely forgotten. Each year, the Romans celebrated a civic festival in honor of Neptune called the Neptunalia. This festival takes place on the 23 rd of July and celebrated the control of catchments of water and drainage. The festival was celebrated during the peak of summer, when the threat of drought was very real, thus emphasizing the significance of Neptune’s control over the city’s fresh water. Unfortunately, little is known today about the Neptunalia, though we are told that during the festival, the Romans would use the branches of trees to build tents or huts. It is assumed that the celebrants would feast and drink in these temporary structures.

Like his Greek counterpart, Neptune was also the god of horses, and believed to oversee the sport of horse racing. In this guise, the god was known as Neptune Equester. According to one myth, Neptune is credited with the invention of the chariot, alongside Minerva (Athena to the Greeks). The god, after all, is said to travel over the seas in a chariot drawn by horses (sometimes represented with fish tails).

A statue of a helmeted Minerva, who Neptune competed with. (Jan Frans Deckers / CC BY-SA 4.0)

A statue of a helmeted Minerva, who Neptune competed with. (Jan Frans Deckers / CC BY-SA 4.0 )

According to another myth, Neptune was not collaborating with Minerva, but in competition with her. In this myth, the two deities were in conflict, as both wanted the capital of Attica to be named after themselves. In order to resolve the dispute, it was decided that the city would be named after the god who bestowed the most useful gift upon the city. Whilst Minerva gave the city’s inhabitants the olive tree, Neptune created the horse. In the end, Minerva’s gift was deemed to be the more useful of the two.  

In another horse-related myth, Neptune transforms into a horse to rape his sister, Ceres (Demeter to the Greeks). This was because the goddess had transformed into a mare in order to escape from Neptune’s persistent, but unwanted, advances. As a consequence, Ceres gave birth to a daughter and a black mare.

As the god of horses, Neptune has been compared with another ancient Italian deity, Consus. Although he is thought to have been an agricultural god, Consus was also associated with horses, and had an underground altar at the first turn at the southeast end of the racetrack in the Circus Maximus. Mules and horses were honored on his festival days, as they were crowned with garlands, and given rest from work. Chariot races, albeit with mules, rather than horses, were presided over by the god’s human priests. Consus’ fate was opposite from that of Neptune, i.e. his status dropped from being a major to a minor deity in later times.

A cameo showing Poseidon as the gymnasiarch of the Isthmian Games as the god of horses. (Vassil / CC0)

A cameo showing Poseidon as the gymnasiarch of the Isthmian Games as the god of horses. (Vassil / CC0)

But Neptune Never Reached Poseidon’s Level Of Prestige

Despite being elevated to the status of a major god in the Roman pantheon, Neptune never attained the level of prestige that his Greek counterpart enjoyed. For example, in Athens, Poseidon was the most important god after Athena. Additionally, the cult of Poseidon existed throughout ancient Greece. The god’s most important cult center was his sanctuary near Corinth, where the Isthmian Games were held. Other important cult centers dedicated to Poseidon were Helike, in Achaea, and Onchestus, in Boeotia.

The cult of Neptune, however, did not spread throughout the Roman world to such an extent. Nevertheless, there were two major temples in Rome dedicated to Neptune. One of these stood near the Campus Flaminus, the Roman racetrack at the southern end of the Campus Martius. This temple was built in 25 BC and contained a famous sculpture of a marine group by the ancient Greek sculptor, Scopas. It is speculated that the location of this temple was influenced by Neptune’s role as the god of horses. The other temple was the Basilica Neptuni, or the Basilica of Neptune, located on the Campus Martius. This temple was dedicated by Agrippa, Augustus’ close friend and right-hand man, to Neptune in commemoration of the naval victory over Mark Antony and Cleopatra at the Battle of Actium. This shows that by this time, Neptune had replaced Fortuna as the god responsible for giving the Romans victory at sea.

Apart from that, there was also a sanctuary to Neptune between the Palatine and Aventine Hills, where a stream once flowed. This may be a reference to his role as a freshwater god. More generally speaking, Neptune was the natural god for seafarers to pray to, as they believed that he would grant them safe voyage across the seas.

The Portrait of Andrea Doria as Neptune by Agnolo Bronzino is arguably the most famous example of a seafarer portrayed as the god of the sea. (Sailko / CC BY 3.0)

The Portrait of Andrea Doria as Neptune by Agnolo Bronzino is arguably the most famous example of a seafarer portrayed as the god of the sea. (Sailko / CC BY 3.0 )

In The End, Neptune’s Influence Was Greater Than Poseidon’s

Whilst Neptune was not as significant a god to the Romans as Poseidon was to the Greeks, the former’s legacy is felt in Western culture even till this day. For instance, Neptune is still associated with the sea, and commonly regarded as its personification. For instance, Thomas Fuller, an English physician who lived during the 17 th / 18 th century AD, has “Bacchus hath drown’d more Men than Neptune” in his Gnomologia, a collection of proverbs.

Neptune also became synonymous with seafarers, who were sometimes depicted as this ancient god. The Portrait of Andrea Doria as Neptune by Agnolo Bronzino is arguably the most famous example of a seafarer portrayed as Neptune.

Moreover, in 1846, a new planet, the eighth one from the Sun, was discovered. Although the names Janus and Oceanus were proposed, it was eventually called Neptune. This was due to the planet’s bluish color, and the trend in naming the heavenly bodies after figures from classical mythology. In the case of the planets, it is clear that they are named after the Roman gods, rather than their Greek counterparts.

In short, Neptune is a figure from ancient times who still has relevance in today’s world. From his origins as a god of fresh water, he was transformed into the god of the sea through his association with Poseidon. Whilst his Greek counterpart faded away into history, remaining largely in the realm of mythology, Neptune’s legacy continued in the centuries that followed. Even today, his influence can be felt in various areas, including language, art, and astronomy.

Top image: One of the many statues of Neptune, Roman god of fresh and sea water and more.    Source: eurobanks / Adobe Stock

By: Wu Mingren


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