The Birth of Merlin, or, The Child Hath Found his Father is a Jacobean play, probably written in whole or part by William Rowley. It was first performed in 1622 at the Curtain Theatre in Shoreditch. It contains a comic depiction of the birth of the fully grown Merlin to a country girl, and also features figures from Arthurian legend, including Uther Pendragon, Vortigern, and Aurelius Ambrosius.
The 1662 first edition, a quarto printed by Thomas Johnson for the booksellers Francis Kirkman and Henry Marsh, attributed the play to William Shakespeare and William Rowley. The Birth of Merlin is thus one of two plays published in the seventeenth century as a Shakespearean collaboration, the other being The Two Noble Kinsmen. Most scholars reject the attribution to Shakespeare and believe that the play is Rowley's, perhaps with a different collaborator. The play has occasionally been revived in the modern era, for example at Theatr Clwyd.
The Birth of Merlin shares a significant relationship with Cupid's Revenge, a play in the Beaumont and Fletcher canon. Large-scale resemblances in plotting—the missing prince, the ruler and his heir who fall in love with the same woman—could be explained through derivation from common sources; but these larger-scale elements are supported by specific lines and passages that occur in both plays. Compare, for example, "Wilde-fire and Brimstone eat thee!" in Merlin, III,vi,108, with "wild-fire and brimstone take thee" in Cupid's Revenge, V,ii, 49. Other common passages occur in Merlin, II,ii,35–9 and 72–81 and III,vi,83–4, and Cupid's Revenge, I,v,5–11, IV,i,2–7, and V,ii,44–8.