I have been working on a "single name study" researching the Udall name and variances for some time. There is a long tradition of the family in the east end of London and south of the Thames. The "elder" branch of the family moved in the area from Norfolk in the 1300's.The generally accepted history is that the family came from the lake district into Norfolk in the 1100's and from there into Surrey and Hampshire in 1300's. The earlier spelling of the name was typically Uvedale. The name started chanigng to Udall in the 1500's. If you are interested in sharing research drop me a line at home.