This fifteenth- century history, entitled “The total of years from the first man until our generation” begins with Adam, but covers the world's first 6,712 years up to the Latin capture of Constantinople (1204) in a few brief paragraphs that list the lengths of time between major figures. A further five paragraphs bring the narrative to the fourteenth century where the author switches to a fine- grained level of detail. The history covers in earnest the period 1341– 1462. The text breaks off suddenly in the midst of describing the Ottoman siege of Mytilene. Originally, Doukas's history contained no internal divisions, however, the text's first editor, Boullialdus, divided it into chapters.

Doukas's descriptions of various characters in his history are morally judgmental, so that history becomes a series of clashes between the virtuous and the wicked. John Kantakouzenos is noble and good, while Mehmed II is bloodthirsty and depraved. Fortune plays a recurring role as an irresistible force that explains why success and failure do not track neatly with virtue and vice. Simultaneously, the sins of the Romans ultimately account for their misfortunes. Doukas provides lurid descriptions of Turkish atrocities during the capture of Thessaloniki and Constantinople. His history does, however, admit virtuous Turks, such as Murad II, and corrupt Romans, such as Alexios Apokaukos.

The text argues ardently for the need for union between the Catholic and Orthodox churches and portrays Mehmed II's conquest of Constantinople as divine punishment for the failure of the Romans to support the Union of Florence. It is Doukas who attributed to the anti- unionist Grand Duke Loukas Notaras the famous line that “it would be better to see the turban of the Turks reigning in the center of the city than the Latin miter.”

Our knowledge of the historian Doukas derives from his history. The author's grandfather, Michael Doukas, was a supporter of John VI Kantakouzenos in the civil war of 1341– 1347. Michael was forced to flee Constantinople in 1345 and went to Ephesus where he was protected by the Turkish emir of Aydin. Doukas the historian mentions that he was employed as a secretary by the Genoese magistrate of Nea Phokaia, Giovanni Adorno, in 1421. Later he worked for the Genoese Gattilusi family, owners of the island of Lesbos.