Baron Darcy de Knayth is a title in the Peerage of England. It was created in 1332 for John Darcy (or D'Arcy) with remainder to his heirs general, allowing daughters to inherit.^[1]

At the death of the sixth baron, the barony fell into abeyance between his two daughters, which the Sovereign terminated in 1641 in favour of Conyers Darcy, as he was also an heir of the abeyant Barony Darcy de Darcy (created 1509). He also successfully petitioned for the termination of the abeyance of the Barony of Conyers in his favour, and both baronies were considered new creations, with remainder to his heirs male. He was called to parliament as Baron Darcy and Conyers.^[1]

His son, also named Conyers Darcy, was granted the title of Earl of Holderness. The two titles remained united until the death of the fourth earl, when the earldom became extinct, while the baronies were claimed by his daughter, Lady Amelia. Lady Amelia was briefly married to the future fifth Duke of Leeds, and the sixth and seventh Dukes held the baronies de jure.^[1]

At the death of the seventh Duke of Leeds in 1859, the two baronies separated from the dukedom. Sackville Lane-Fox, eldest son of the 7th Duke of Leeds' eldest daughter, claimed the baronies de jure, which again became abeyant upon his death in 1888. The abeyance for the Barony of Conyers was terminated in 1892 in favour of Lane-Fox's eldest daughter Marcia Pelham, Countess of Yarborough. On 29 September 1903, the abeyance of the Barony of Darcy de Knayth was terminated in favour of Lane-Fox's younger daughter, Violet Herbert, Countess of Powis. At the same time, the 1641 ruling, considering the titles new creations only for the heirs male of Conyers Darcy, was reversed, and it was ruled that both baronies were to be held in remainder for heirs general.^[1]