Short-lived as their dynasty was, the Flavians were effective. The Flavian propaganda is an example of how to build a brand the sells for the next 2,000 years by keeping everything simple and commonsensical.
When Vespasian rose to power in 69 AD, he knew he had a legitimacy issue – he had to base his claim to the throne on something more than just the sheer strength of his legions. So he gathered his team for a brainstorming session and came up with a concept for the emotional appeal (“I am emperor because I was destined to be.”) and a second one for the logical appeal (“I am simply better than those before me. You don't want to roll the dice again and replace me, because chances are, you'll do much, much worse.”). Clear and simple – it's advertising, not rocket science. Then he hired a good team of copywriters and designers and set to work.
Oracles, Prophecies and Gods
People from the city of Rome as well as those from the provinces were suckers for omens and prophecies, so it seemed like a good place to start. And prophecies were everywhere, it was just a matter of turning them in the right direction.
Titus, the good and ugly Flavian
For instance, there was a lot of fuss about an ancient prophecy from the East, that the new ruler of the world would come from Judaea. Excellent, both Vespasian and his son Titus fought in Judaea, so they put this to use (and why not, others would do it as well).
The oracle on Mount Carmel told Vespasian he would succeed at everything he attempted. It's exactly the kind of informative and helpful answer you might expect from a fortuneteller, but it received a lot of attention after Vespasian's legions made it true.
And then we have Yosef Ben Matityahu, also known as Titus Flavius Josephus (notice that he's named Flavius? It's not a coincidence.) Josephus was a small-time leader in the Jewish rebellion, and, when captured by Vespasian, managed to save his life by predicting the general's future successes: “Thou, O Vespasian, art Caesar and emperor, thou, and this thy son. Bind me now still faster, and keep me for thyself, for thou, O Caesar, are not only lord over me, but over the land and the sea, and all mankind”. Yadda yadda yadda. Vespasian kept Josephus around (which must have been a drag, if the man talked like he wrote), and released him only after the prediction became true. If this incident is true, it makes you wonder whether Vespasian's ascension wasn't a self-fulfilling prophecy after all.
Domitian, the bad and slightly less ugly Flavian
Then there was the issue of deification. The Julio-Claudians started to present themselves and their families as gods in the provinces, and were also deified in Rome after their deaths (the lucky ones, at least). Vespasian, with his bathroom humor, didn't seem to care much, but couldn't stop the spreading rumors that he was healing the sick and raising the dead in Egypt (right). Both his sons understood the importance of the imperial cult for the provinces, and enforced it consistently and coherently, though Domitian would not make it in the Pantheon. (Anyway, the position of taxation god was still open, and who better to take it than Vespasian?)
The Writing Team
Tacitus, Suetonius, Pliny the Elder and Flavius Josephus. Do I need to say more? Let's face it, it's a killer copywriting team. Though we know that Tacitus, Pliny and Josephus were deeply indebted to the Flavians, the portraits they paint and the descriptions of the era are just so good, you can't help but follow their agenda. So they were paid to write about a product. That doesn't mean they didn't believe it it, does it?
Suetonius also came from a family which, traditionally, was on the Flavians' side (his father fought against Vitellius), but he probably didn't need any incentives: he had such a blast trashing the emperors that preceded Vespasian, he could afford to take a break and praise someone for a change.
It's funny to watch Suetonius shredding Galba to pieces for being cheap, and then jumping through hoops to justify the same trait in Vespasian. And to see Tacitus saying that Vespasian was the first to become a better man after obtaining the supreme power. Hah. It must have been incredibly painful for Tacitus to admit that anybody or anything could change for the better.
With Titus they had fewer problems: he was a good emperor because he was young and died before he had a chance to mess up. A minor issue like one million dead in the siege of Jerusalem should not make us think otherwise.
As for Domitian, you'd think the propaganda failed – they called him the bald Nero and struggled to make him look like a paranoid tyrant, but modern historians fought really hard to rehabilitate his image – and I suspect it has a lot to do with the fact that all Flavians appear as likable chaps today. Maybe we're not convinced any longer that they rescued the empire from total chaos and destruction, but we can certainly relate to their down to earth approach to ruling an empire. All three of them look like fiscal inspectors with a sense of humor.
Surely, not every piece of the puzzle fits in so smoothly. Some people must have been criticizing the Flavians – but we don't hear much of them these days. We know Vespasian banished philosophers from Rome, probably because they were over-complicating things, messing up his nice and simple concepts and confusing people. One convinced republican senator, Helvidius Priscus, was put to death, and later Domitian would complete the circle by killing Herennius Senecio, the man who wrote Priscus' panegyric.
The Images
Writers are good, but images are still worth a thousand words, even when those words come from some of the best writers in ancient times. Rome was pretty messed up after the recent fires and the destruction caused by riots and fighting on the city streets in the year of 69, so the Flavians undertook massive construction projects – what better proof that the empire was stable and peaceful than some huge entertainment venues?
They distanced themselves from the hated Nero by tearing down his infamous Domus Aurea and replacing it with the Flavian amphitheater, better known today as the Colosseum – the number one symbol of the Roman empire. Same as with everything else they did, the key was consistency: Vespasian clenched his teeth and provided the funds for the construction, Titus pushed forward with an early inauguration and Domitian finished it by adding a fourth level. The Arch of Titus, the Flavian Palace, a new stadium, the Temple of Vespasian and Titus and several other buildings added up and reinforced the main themes of the propaganda.
There's also much to be said about the carefully designed coins from this age, but I don't want to use up more than my fair share of Internet space today, so I'll just say this: they clearly show that all three Flavian emperors were massive, solid individuals, same as everything they did. And ugly as hell, too - which is a problem for Titus, who got so may praises on account he was charming. We can only hope he had an incredible personality, to compensate for that porcine look.