Recorded as Yelloly, Yellowlea, Yellowlee, Yellowlees, Yellowley, and others, this is an English surname. It is locational and the translation is probably 'rough farm' from the pre 7th century Olde English word 'girwe' meaning rough or muddy and 'leah' a fenced area suitable for agriculture - a farm. The only problem that we have is that there is no such place in any of the known surname spellings. From this we conclude that the surname is one of the ever growing list of locational names which originate from now 'lost' medieval villages or even small towns. Todate some three thousand have been identified in the British Isles and more are added almost daily. As to why places have disappeared has been the subject of several book, but the usual culprits are changes in farming practices, urbanisation, coastal erosion as well as more exotic reasons such as war and the Great Plagues of the 14th to 17th centuries. In this case early examples of the surname recordings taken from surviving registers of the city of London include Thomas Yellowley who married Isable Edin at St Giles Cripplegate on January 16th 1724, and in Cumberland Henry Yellowlee, who married Elizabeth Smith at St Mary's Carlisle, on September 23rd 1845.