A chronicle composed shortly after 628, the point at which its record ended. The Vatican MS from which it is known is mutilated, ending in 627. The work takes its usual name from treatises about chronology and the calculation of Easter in its introduction. The birth of Christ is dated in the “year of the world” 5507, and His crucifixion in 5540. The chronicler expands the framework by excerpts from many sources, e.g., the Chronographies of, the Bible, works of Eusebius and Epiphanius, the Fasti consulares, acts of the martyrs. For Byzantine history he follows John Malalas to the year 532, and after 600 records events contemporary with his own life. His name is unknown. His work was much read and used in the Byzantine period. It is of great value, especially for the later history, and for the history of chronological techniques and theories in the ancient Christian world.