Recorded as Lugden, Lugdin, Lugsden, Lugsdin, Lugsdon and no doubt other spellings, this is an English locational surname. It originates from some place whose name is or was, the same as at least one of the surname forms, but we have not been able to provide a match. This is not a unique situation. It is estimated that at least three thousand surnames of the British Isles and including Ireland, originate from now "lost" medieval villages of which this seems to be another example. The place name would seem to translate as "light valley" from the Olde Welsh word lugg meaning light, and the pre 7th century English denu, a valley or depression. As to why so many places have disappeared over the past five centuries has been the subject of many books, but changes in agricultural practices and particularly the introduction of sheep farming, as well as urbanisation, the great plagues, war and even coastal erosion have all played some part. The surviving early church registers of the city of London provide a number of examples of the surname recordings. These include Elizabeth Lugden who married James Lantram at St Dunstans Stepney, on March 27th 1638, and two centuries later that James Lugsdin christened at St James Bassishaw on May 20th 1828