Answer:
Vincent was in the asylum at Saint-Rémy and his behaviour was very erratic at the time
and how Starry Starry Night got it name is the morning star
True, Byzantium was the Eastern Roman empire, that persisted long after Rome's fall. Its capital was Constantinople, and the Eastern Roman Empire fell in 1453, with the sack of Constantinople by the Ottoman Turks.
By what I've learned, it's called a HYMN