The Unnatural Combat is a Jacobean era stage play, a tragedy written by Philip Massinger, and first published in 1639. No hard data on the play's date of origin or initial theatrical production has survived. Scholars estimate a date in the early 1620s; "There is a strong case for a late 1624 or early 1625 date for the play." The play was entered into the Stationers' Register on 14 February 1639, and published in quarto later that year by the bookseller John Waterson; the title page states that it was acted by the King's Men in the Globe Theatre. The quarto also bears Massinger's dedication of the play to a personal friend, Sir Anthony St. Leger (or "Sentleger").