I found a similar thing in that a surname I am researching Luffman is unknown in the north of England before 1798, the name is at its least uncommon in the counties of Dorset, Somerset and Wiltshire. It became established in Lincolnshire as a result of movements of the Somerset Militia to Lincolnshire to resist potential invasion by the French, apart from that there does see, to have been migration from southwest to northeast along the line of the Roman Road, the Fosse Way between Exeter and Lincoln, so I think a connection is quite likely, and there may be an association between the surname and other towns on this route besides Leicester.
