And Sasan might have exalted company. It was whispered that Constantine had turned to the Christians only because their priests had offered him the hope of absolution. Beheading your eldest son, and having your wife suffocated in a hot bath, would weigh on any conscience. It would be a strange deity that overlooked such sins in his judgement of a soul.

Thank God, the service was over. Sasan was hungry. Fasting did not agree with him.

Outside, the late evening sunshine fell in bands under the portico. Sasan’s grandson led him to the litter that would convey him back to his house overlooking the Bosporus. It was pleasant there by the water. The house had been one of those gifts offered by Constantine to those senators prepared to leave Rome for his new capital. Sasan’s domicile, like his piety, was a result of worldly calculation.

The summons to the consilium of the Emperor just before Easter had been an unexpected honour. Constantine was preparing for war with Persia. Quite what advice Sasan might have been expected to proffer was a mystery. He had been an eleven-year-old child when he had left Persia seventy-two years before. His role as a diplomatic hostage had been eclipsed long ago when Hormisdas, the brother of the King of Kings Shapur II, had fled to Rome.

Sasan had been grateful that Hormisdas further removed him from attention. Until recently he had enjoyed the company of Hormisdas. But now he kept his distance. Constantine had proclaimed his own nephew Hannibalianus King of Kings. The projected campaign in the east was to place Hannibalianus on the throne in Ctesiphon. Hormisdas had become unnecessary, perhaps something of an embarrassment, and had not been invited to the consilium. Perhaps Sasan, as a member of the Persian royal house, had been thought to give some spurious legitimacy to the whole affair.

Truth be told – and one must abhor the Lie – Sasan knew his effect on relations between Rome and Persia had always been negligible. The year after he had been rescued from the Castle of Silence there had indeed been a war. Thousands of men, women and children had suffered and died. Roman troops had sacked Ctesiphon. But the war had been fought by Odenaethus, the ambitious Lord of Palmyra, who had commanded Rome’s eastern provinces. It had not dragged the Emperor Gallienus from the west. Odenaethus had campaigned alone to free Valerian from Persian captivity. The Lord of Palmyra had failed. There had been no attempt to set up the young Prince Sasan as King of Kings. The war would have been fought if Sasan had remained a prisoner in the Castle of Silence.