Thomas Langley (c.1363-1437) was Bishop of Durham 1406-1437. He is shown kneeling before a prayer-desk (prie-dieu), facing the large figure of St Cuthbert, with his hands raised in prayer. Langley began his career as a clerk for John of Gaunt, the father of Henry IV, and served as a royal counsellor and diplomat for the Lancastrian kings Henry IV, V and VI. The Latin inscription beneath Thomas Langley clearly identifies him as the donor of the window: “[Pray for the soul of] Thomas Longley, bishop of Durham, who [caused] this window [to be made]”. Langley also contributed to the glazing of York Minster's clerestory and library, as well as donating numerous other windows at Durham Cathedral Priory, which housed Cuthbert's shrine.