What Time Period Did The Fel Temp Rep Coins Refer To?

The series was made from 348-358, after Constantine II was killed in civil war, and through the deaths of Constans and Gallus, both from assasination or execution. They were probably promising the return to the stability under Constantine I, "Just as soon as I take care of this usurper".

I am not aware if the Christian emperors looked up to the pagan emperors of the golden age, but Julian "The Apostate" certainly tried to model his rule on Pius, Hadrian, Aurelius et al.

That's a good one, Sap

Anyway, thanks for explaining!

There are other FEL TEMP reverses, such as the Phoenix, but they can all be interpreted in much the same way.

The Phoenix, rising from the ashes, was a common symbol of rebirth and resurrection. The message here is: the Empire might be in a sorry state now, but it will be reborn anew, back to the way it was when we ruled the world. Kind of a "The South will rise again" sentiment, or perhaps more like "we had to destroy this village to save it".

A similar theme would be interpreted from the reverse type with the Emperor, holding a phoenix and standing on a ship, piloted by Victory; except here, I would see it as a more personal claim of the emperor: The Empire was left to wrack and ruin by those who came before me, but I'm here now, and I will bring victory, and restore the Empire back to the way it was.

Don't forget, it was obvious to the people living in the Late Empire, especially in the West, that the Good Old Days really were better. Some of the roads that used to keep the Empire unified were crumbling due to lack of maintenance. Some of the aqueducts that used to bring water to the big cities stopped working and no-one knew how to repair them. And, perhaps most significantly, the wealthy used to be able to live in peace in their country villas and unwalled towns, but now have to live in fortified settlements to protect themselves from barbarian raiders.