During his exile Ludlow wrote an autobiography entitled "A voyce from the watch tower". After his death his manuscript was obtained by Slingsby Bethel, who had visited him in Switzerland. Part of it, covering the years 1660–77, was discovered at Warwick Castle in 1970 and is now in the Bodleian Library. A heavily rewritten and shortened version of "A voyce" appeared as "The Memoirs of Edmund Ludlow" in 1698–9 in three volumes. The historian Blair Worden has surmised that the editor was the deist John Toland. The "Memoirs" were part of a range of late seventeenth-century publications printed by John Darby, including the "Discourses" of Algernon Sidney and the works of John Milton and James Harrington. In the "Memoirs" Ludlow's puritanism is virtually written out, and his views changed to make him a Whig-like secular republican. Until the 1970s the "Memoirs" were generally assumed to be authentic – there were editions in 1720–22, 1751, and 1771, with a scholarly edition by C.H. Firth in 1895. As a result, the Memoirs have been used until very recently as a major source for historians of the seventeenth century, with only the rediscovery of Ludlow's original manuscript prompting a reassessment.