The Dionysiaca (, Dionysiaká) is an ancient Greek epic poem and the principal work of Nonnus. It is an epic in 48 books, the longest surviving poem from Greco-Roman antiquity at 20,426 lines, composed in Homeric dialect and dactylic hexameters, the main subject of which is the life of Dionysus, his expedition to India, and his triumphant return to the west. Composition The poem is thought to have been written in the 5th century AD. The suggestion that it is incomplete misses the significance of the birth of Dionysus' one son (Iacchus) in the final Book 48, quite apart from the fact that 48 is a key number as the number of books in the Iliad and Odyssey combined. The older view that Nonnus wrote this poem before conversion to Christianity and the writing of his other long poem, a verse paraphrase of St John's Gospel, is now discredited, since a host of indications point to the latter being the earlier work and because it misses the eclecticism of late antique culture. Editors have pointed out various inconsistencies and the difficulties of Book 39 which appears to be a disjointed series of descriptions, as evidence of lack of revision. Poetic models The primary models for Nonnus are Homer and the Cyclic poets; Homeric language, metrics, episodes, and descriptive canons are central to the Dionysiaca. The influence of Euripides' Bacchae is also significant, as is probably the influence of the other tragedians whose Dionysiac plays do not survive. His debt to poets whose work survives only in disjointed fragments is far harder to gauge, but it is likely that he alludes to earlier poets' treatments of the life of Dionysus, such as the lost poems by Euphorion, Peisander of Laranda's elaborate encyclopedic mythological poem, Dionysius, and Soteirichus. Reflections of Hesiod's poetry, especially the Catalogue of Women, of Pindar, and Callimachus can all be seen in the work of Nonnus. Theocritus' influence can be detected in Nonnus' focus on pastoral themes. Finally, Virgil and especially Ovid seem to have influenced Nonnus' organization of the poem. Influence Nonnus seems to have been an important influence for the poets of Late Antiquity, especially Musaeus, Colluthus, Christodorus, and Dracontius. He remained continuously important in the Byzantine world, and his influence can be found in Genesius and Planudes. In the Renaissance, Poliziano popularized him to the West, and Goethe admired him in the 18th century. He