This unusual surname is apparently recorded in many forms including Malby, Maleby, Mallaby, Melby, Melbury and Milby. It is English and locational. It originates from the the diminished hamlet of Milby, near Boroughbridge, in the county of North Yorkshire, a place that was originally on the route of the Great North Road constructed by the Romans in the 1st century a.d, and where the first bridge was built. The route was changed in about the 13th century when the stone bridge at Boroughbridge was built, and sometime later Milby lost its mill, and gradually died away until today it consists of only half a dozen cottages and farms. The name means the mill by the farm from the Norse-Viking word "byr", the area being part of the kingdom of Northumberland ruled by the Vikings for several centuries. Locational surnames were by their very nature usually "from" names. That is to say surnames given to people after they left their original homes and moved elsewhere, one of the easiest forms of identification being to call strangers by the name of the place from whence they came. Spelling through the centuries being at best erratic, and local dialects very thick, lead to the development of "sounds like" spellings. Examples of the surname recordings taken from various surviving church registers and showing the name development over the centuries include: Peter Milbie christened at Aldborough, Yorkshire, on November 6th 1540, Richard Maleby, a witness at St Johns Hackney, in Greater London, on October 19th 1698, and Margaret Mallaby, christened at the church of St Mary le Bow, in the city of London, on June 29th 1728.