Sol, Roman deity of the sun. His cult seems to have been relatively unimportant until promoted to a state cult under the Aurelian emperors as Sol Invictus.
The Latin name Sol is cognate to the Etruscan Usil, Sabine Ausil, Sanskrit Surya, Germanic Sol, and Greek Helios.
Varro mentions Sol Indiges as one of the 12 principal agricultural deities.
According to tradition, the Sabine king Titus Tatius introduced the worship of Sol to Rome after the conclusion of peace between Romulus and the Sabines
The Sabines settled on the Quirinal, and the altar of Sol there was one of the altars established by Titus Tatius.
For the early Romans, Sol was an important symbol of the amalgamation of Latins and Romans. As Aeneas was the supposed ancestor of the Romans, so Odysseus was the ancestor of the Etruscans and Latins. Latinus, the eponymous ancestor legendary hero of the Latins, was said to have been a son of Odysseus and Circe, who was herself the daughter of Helios (Sol).
Under the Republic, the cult of Sol Indiges was a sacrum gentilicum of gens Aurelia (originally the Sabine gens Auselii), who claimed descent from the god.
Probably the Romans made an evocatio of Sol at some point during the early third-century conquest of the Sabines, and the Aurelii, as the Sabine family that superintended the cult, acquiesced in Sol’s removal to Rome.
At an early date Sol came to be identified with Janus. Janus and Jana were worshipped as sun and moon, and were regarded as the highest of the gods, receiving their sacrifices before all the others.
By the time of the early Empire, Sol had been partially syncretized with the Greek Apollo. In Horace’s Carmen Saeclare, the poet addresses Apollo and Diana. Apollo he calls both Phoebus and Sol. Apollo and Diana carry the prayers of the people to the throne of the gods. Horace also mentions Sol in his Odes.
The worship of Sol Invictus was elevated to a state cult by the emperor Aurelian in 274. He built a temple and founded a second pontifical college, the pontifices Solis, pontiffs of the Sun, to administer the rites.
Many older works erroneously suppose the cult of Sol Invictus was the oriental cult of Elagabalus imported to Rome. Modern research has shown that the cult is, however, autochthonous at Rome. The type of Sol Invictus, though not the name, appears on imperial coinage from the time of Septimius Severus onwards.
Sol Invictus was a powerful symbol for the Romans of the late Empire: each evening he is forced apparently to submit to the powers of darkness, but he reappears each morning as the eternal victor. Christian scholars have frequently seen Sol Invictus and Mithras as prefigurations of Christ.
Anciently, Sol seems to have been the god of the agricultural year. In the time of the Republic the worship of Sol Indiges was joined with that of Luna, the moon. Priests are typically attested as both Solis et Luniae.
Sol had sacred grove at Lavinium, probably his original home. There were also local shrines to Sol Indiges in the rural areas of Sabinium, Samnium and Etruria.
At Rome, Sol had a temple on the Quirinal near the temple of Quirinus. Quintilian describes it as a pulvinar, a place where a deity is carried or entertained at a banquet (ad lectisternium).
Sol and Luna shared the Templum Solis et Lunae, a shrine (aedes) in the Circus Maximus. The two of them were patrons of racing. Augustus set up an important solar monument, the obelisk of Ramses II brought from Heliopolis, on the spina of the Circus Maximus, probably on the axis of the templum.
An epigram quoted by Cicero shows that the rising sun was greeted each morning.
The prayer had to be spoken while facing east: ad ortus, ad orientum.
An elite legion raised by Constantius I in the third century was named the Solenses (sacred to Sol).
The feria of Sol Indiges and dedication (dies natalis) of the temple on the Quirinal was celebrated August 9th. . The publicum was August 8th.
The dedication of the Templum Sol et Luna at the Circus Maximus was celebrated on August 28th.
Sol was also honored on December 11th, one of the dies agonales. A different god was honored on each of these days, Janus on January 9, Liber Pater (Mars?) on March 17, (Vediovis?) on May 21, and Indiges on December 11.
On each of the dies agonales a ram was sacrificed in the Regia.
The Imperial cult of Sol Invictus celebrated the Dies Natalis Solis Invicti, the Birthday of the Unconquered Sun, on December 25. This date was considered to be the date of the winter solstice.
Under Greek influence, the image of Sol was derived from his equivalent Helios. Sol was represented as driving a quadriga, a four-horse chariot. Sol appears in this form on a denarius of gens Manlia in 135 BCE.
Sol’s cult partner Luna is represented driving a biga, a two-horse chariot.
Gaston H. Halsberghe, The Cult of Sol Invictus (1972).
Steven E. Hijmans, "The Sun which did not rise in the East: The Cult of Sol Invictus in the Light of Non-Literary Evidence", BABesch: Bulletin Antieke Beschaving, 71 (1996), 115-150.
Steven E. Hijmans, "Sol Invictus, the Winter Solstice, and the Origins of Christmas", Mouseion, Number 47/3 (2003).