Dating from the time of the Etruscans, a diviner or , was always consulted, and it was considered dangerous to ignore the omens.
Spurinna, a Roman soothsayer, read animal entrails and foresaw Julius Caesar’s death on the Ides of March.
The first citizens of Rome also believed they were watched over by the spirits of their ancestors.
Initially, a Capitoline Triad (possibly derived from a Sabine influence) were added to these “spirits" - the new gods included Mars, the god of war and supposed father of Romulus and Remus (founders of Rome); Quirinus, the deified Romulus who watched over the people of Rome; and lastly, Jupiter, the supreme god.
They, along with the spirits, were worshipped at a temple on Capitoline Hill.
Later, due to the Etruscans, the triad would change to include Jupiter who remained the supreme god; Juno, his wife and sister; and Minerva, Jupiter’s daughter.
While this fusion of Roman and Greek deities influenced Rome in many ways, their religion remained practical.
Next, Jupiter’s wife/sister was Juno, for whom the month of June is named - she was the equivalent of the Greek Hera.
Besides being the supreme goddess with a temple on Esquiline Hill, she was the goddess of light and moon, embodying all of the virtues of Roman matron hood - as Juno Lucina she became the goddess of childbirth and fertility.
When Roman Commander Publius Claudius Pulcher ignored the omens - refusal of the sacred chickens to eat - before a battle during the First Punic War, he was defeated, as was his military career.
As the empire expanded across the Balkans, Asia Minor and into Egypt, Roman religion absorbed many of the gods and cults of conquered nations, but the primary influence would always remain Greece.