The Christmas Ordinary, printed in 1682, is a raucously lively Jonsonian comedy of uncertain date and authorship, which appears to have been performed by undergraduates at Trinity College, Oxford. This article combines three sources of information: 'W. R.'s remarks about the identity of the author in the preface to the 1682 printing; G. E. Bentleys work establishing through internal evidence that the play appears to date from the mid-1630s; and a partial manuscript of the play in the British Library, unknown to Bentley, which attributes The Christmas Ordinary to 'H. B.'. This article proposes that 'H. B.' is Dr Henry Birkhead (1617-96), a poet and dramatist best remembered today as Founder of the Oxford University Professorship of Poetry. Corroborating evidence for the attribution proposed here includes the fact that Birkheads own Latin poetry contains hitherto unnoted translation from The Christmas Ordinary. The article pursues the consequences of this proposed attribution, which locates The Christmas Ordinary more firmly in the aspirations, fears, and resentments of the culture from which it comes, the Oxford University of the 1630s.