Two fyres on the auter gan she beete,
And dide hir thynges, as men may biholde
In Stace of Thebes and thise bookes olde. (KnT I.2292-94)

Statius was born about 45 A.D. and died about 96; He was the author of the Thebaid, of an incomplete epic of Achilles, and of the Silvae, a collection of occasional poems. His Thebaid, the epic of the struggle of Oedipus' sons, the story of "The Seven Against Thebes," was his most popular work in the Middle Ages, perhaps especially because of what modern critics have regarded as a weakness: "Statius is distinguished among his contemporaries by skill and imagination, but suffers from the tendancy of the time to make great display of learning and rhetorical ornament."
From Oskar Seyffert, A Dictionary of Classical Antiquities (1891). rev. Henry Nettleship and J.E. Sandys, 1956, p. 602. [DE5,S5 1956]

For an edition of Statius' works see:

Statius, with an English translation by J.H. Mozley. Cambridge, Mass. Loeb classical library. 1928-1955. 2 vols. [PA6156.S8 1928x]. The very useful site The Silver Muse, maintained by the Classics Department at the University of Texas, has a good summary of the Thebaid.

For a study of Statius' influence on Chaucer see:

Winthrop Wetherbee, Chaucer and the poets: an essay on Troilus and Criseyde. Ithaca, Cornell U. Press, 1984 [PR1896.W48 1984].

The Thebaid was best known in the Middle Ages in the French romance version:

Le roman de Thebes, ed. Guy Raynaud de Lage. Paris, CFMA 94, 96, 1966- [Widener 27282.69.10] For an English version see John Smartt Coley, The Siege of Thebes: a translation of the Roman de Thèbea lines 1-5172). 1965. [Widener 27282.69.11].

For a Middle English version of the romance, see:

John Lydgate (1370?-1451?), Lydgate's Siege of Thebes, London, Chaucer Society, 1911 [Widener 1183.46].