It's the Chronicle of Christ's Nativity, or the Kalenda Proclamation, a non-too historically accurate attempt to put Christ's birth in some sort of historical (and especially Biblical) context. It's pretty hopeless as a chronology. But it contains a poetry, a spirituality, that makes up for any lack of authenticity.
As Scott says to Ransom Stoddard in The Man Who Shot Liberty Valance, 'When the legend becomes fact, print the legend.'
