Thomas of Walsingham (c.1340-c.1422) was a monk of St Alban’s abbey whose Latin chronicle of the years 1328-88 was long thought lost. It was rediscovered by chance and edited by Edward Maunde Thompson (1840-1929), whose edition, published in 1874 with English side-notes, is based on a Harleian manuscript he found in the British Museum, supplemented by Bodleian and Cottonian manuscripts. Walsingham’s chronicle is notable for its scurrilous attacks on John of Gaunt, duke of Lancaster and father of Henry IV. This scandalous material accounts for its suppression by the monks of St Alban’s, who would have been fearful of offending the Plantagenet dynasty. Thompson’s introduction provides a full history of the discovery and comparison of the manuscript sources, a discussion of the contents of the chronicle, and two later English texts based on it. A portion of Walsingham’s Polychronicon, covering the years 1376-7, is provided as an appendix.