What is Ancient Greek novel?

Five ancient Greek novels survive complete from antiquity: Chariton's Callirhoe , Achilles Tatius' Leucippe and Clitophon , Longus' Daphnis and Chloe , Xenophon of Ephesus' Ephesian Tale , and Heliodorus of Emesa's Aethiopica. There are also numerous fragments preserved on papyrus or in quotations, and summaries in Bibliotheca by Photius, a 9th-century Ecumenical Patriarch. The titles of over twenty such ancient Greek romance novels are known, but most of them have only survived in an incomplete, fragmentary form. The unattributed Metiochus and Parthenope may be preserved by what appears to be a faithful Persian translation by the poet Unsuri. The Greek novel as a genre began in the first century CE, and flourished in the first four centuries; it is thus a product of the Roman Empire. The exact relationship between the Greek novel and the Latin novels of Petronius and Apuleius is debated, but both Roman writers are thought by most scholars to have been aware of and to some extent influenced by the Greek novels.