No major source can be identified for Titus Andronicus, although one very likely did exist at some point but has been lost to modern readers. There is a possibility that Shakespeare relied upon a poem circulating in 1570, unfortunately titled, A Lamentable Ballad of the Tragical End of a Gallant Lord and of his Beautiful Lady, With the Untimely Death of Their Children, Wickedly Performed by a Heathen Blackamore, Their Servant: The Like Seldom Heard Before. We know that, as a minor source, Shakespeare used Ovid’s tale of Progne and Philomela (as found in Metamorphoses), which he cited almost verbatim in Act IV, Scene I (42) of the play. The dark and troubling plays of Seneca also seem to have inspired Shakespeare as he was crafting his most horrific drama. Of these works, Seneca’s Thyestes seems to have been the greatest influence on Shakespeare.