For Romans, September is the month of sacred games to honor Jupiter Optimus Maximus. Later in the month, the Capitoline Triad, the Gods of State, is honored with a feast. The harvest is finished and now is the time to relax and to focus on matters of government.
For Babylonians, September is the time of the autumn rains. The long hot dry season has finally ended. The fields are being prepared for the barley planting. At this time, the Descent of Inanna is re-enacted to ensure that the land is fertile.
On September 1, Juno Regina, the Queen of Heaven is honored. In 392 BCE, following a vow, Marcus Furius Camillus raised a splendid temple to this Goddess. Using the rite of evocatio, Camillus promised Uni of Veii that if She allowed him to conquer her city, he would build a temple to Her in Rome. Agreeing, Uni left the Etruscan city to become Juno Regina of Roman. She rules the State with Jupiter Optimus Maximus and Minerva as the Capitoline Triad.
JUPITER OPTIMUS MAXIMUS AND THE CAPITOLINE TRIAD
The Ludi Romani are held for Jupiter between September 5 -19. These sacred games (ludi) began in 566 BCE. The Romans held parades, races, and theatrical performances. Contrary to popular belief, there were no gladiatorial combats during the Ludi Romani.
The feast for the Capitoline Triad, known as the epulum Iovis (Feast of Jupiter), is held September 13. Statues of these Gods are dressed, wined, and dined. Traditionally only the Senators and magistrates attended this feast.
INANNA (ISTAR) (Note 1)
At the autumn equinox, Babylonians re-enact the Descent of Inanna. Her Descent into the Underworld is the hinge between the dry and rainy seasons. Inanna dies but is rescued. Since someone has to replace Her in the Underworld, Dumuzi, Her Shephard Consort, goes down for six months. His sister, Geshtinanna, Goddess of Autumn Wines, takes his place the other six months.
Note 1: Inanna has many names – Inana and Istar are well-known.