If you haven’t read “Against the Fall of Night”, by Michael Arnold I highly recommend it. It’s about the Comneni dynasty of emperors.
From the 1953 historical novel “The Dark Angel” by Mika Waltari about the last days of Constantinople during the siege.
{7 February 1453}
…………………….”No, Manuel,” I admitted; “’it’s true. The cannon is on its way. Spring is in the air; soon doves will be cooing and flocks of birds will fly northward over the city. When spring is in full blossom the Sultan will be at the gates of Con stantinople; no power in the world can prevent it.”
“And how long,” he asked, “how long shall we last after that?”
Why should I lie to him? He is old. He is a Greek. I am no physician, but a human being— his fellow.
“A month, perhaps,” I told him. “Or it may he two, Giustiniani is a brilliant soldier. Three months if he matures with his task, as I believe he will. But hardly longer. Hardly longer than that, at best.”
Manuel was no longer trembling. He looked me straight in the eye.
“And the countries of the west?” he asked.
“The Union?”
“With Constantinople even the western nations will be swallowed up in night. Constantinople is the last lamp, the last hope of Christendom. If they allow it to be quenched they will have deserved their fate.”
“And what will be their fate?” he asked. “For give me, master, but I am curious to know, so that my heart may prepare itself.”
“Flesh without spirit,” I said. “Life without hope, the slavery of mankind —a bondage so hopeless that slaves will no longer know they are slaves. Wealth without happiness, abundance without the power to enjoy it. The death of the spirit.”