What was the Roman Imperial Cult?
Well, first of all, throw everything you know about separating religion and politics from each other out of the window. The Roman Imperial Cult is one of the most ingenious ways in global world history of keeping order in an empire. It was a mix of religion, politics and propaganda that is hard to grasp the extent of fully.
Who did they worship?
They worshipped the numen and the genius of the Emperor, but also the genii of the entire imperial family. A loose modern translation would be the life spirit and the soul of the living Emperor. The genius is something that everyone in the empire had, and you could certainly pray to your mother’s genius if you wanted to. The numen was unique to the living Emperor. It was thanks to the numen that the Roman Empire was such a great place. The reason for which they could hold back the barbarians on the borders, enjoy gladiatorial games, walk safely on the streets, and so on.
How did it work?
To keep this immense structure in a constant and working condition it required a mass of different priesthoods and priests, as well as governors who were determined to make sure that everyone followed suit. Very few decisions about they cult emerged from the city of Rome itself. Instead most of the decisions regarding the cult were decided on a local level, either regionally or within a municipality. Thanks to this we have altars showing Gaius and Lucius Caesar, despite them never actually becoming Emperors.
What about the deification?
Only certain Emperors did in fact get deified. Although all Emperors up to and including Diocletian were divus <name>, but only a few of them got the title divi <name> when they died. The case of divi is a complicated matter which has to do with the priesthood flamines. Flamines were priests that belonged to temples, and temples were only allowed to be erected for gods. Certainly not for living Emperors.
They exception to the rule is Tiberius, who refused to have himself treated as a potential god. A refusal that was only acknowledged in the West; the East had a different history of ruler worship and did not play by the same rules as the West. Emperors that were in fact deified were divus Augustus, divus Claudius and divus Vespasianus, among others.
Did any women get deified?
Yes! Most importantly Livia, the wife of Augustus, who died 13 years after her husband. When she died in 27 AD her son Tiberius was Emperor and it has been speculated that it played part in the defification. Nonetheless, Livia Augusta became diva Augusta when she died, one of few women to hold that title.
What did the propaganda look like?
My personal favorite is this statue, called Augustus of prima porta.
Notice they artwork on the breastplate, the stout facial features, the prominent stance and the combination of a breastplate and a toga. Now imagine that it was painted as well.
Most people in the Roman Empire would never have met or even seen the Emperor. Instead this, and images like this one, is what they would be seeing. On coins, statues or similar. What they see is the pater patriae, the father of the fatherland. The man that keeps peace and prosperity in the empire through his wisdom and intelligence.
So, what can we learn from this cult today? The Roman Imperial Cult is a prime example of how a politician can use various ways to get the people on his or her side. It is also a great example of how religion can be used to strengthen the power structure in a state. More than anything it shows us the power of something else, something that distances itself somewhat from both politics and religion – the sense of belonging.
Many people today have trouble finding their true identity. So were the case also when Augustus came to power in the Roman Empire. The Imperial Cult joined together (almost) everyone in a mutual cult worship that both meant that you were Roman and at the same time that the people across the borders were not Romans.
There are lots of things to learn from this cult, a cult that kept the Roman Empire prosperous for 250 years, before the importance of the cult started to decline in favor of Christianity. If you have a hard time imagining it working in modern times, I suggest you take a look at Vladimir Putin.