In PN BdHu:30 it is stated that Carlton
in Bedfordshire is the most southerly example of this Scandinavian place-name
type. I doubt that Mawer and Stenton did a precise check against
Carlton near Saxmundham in Suffolk, for it is a very close race.
Taking the churches of the respective villages as reference points, I make the
grid references and latitudes to be:
Carlton in Bedfordshire SP954552
52.186
Carlton in
Suffolk
TM382640 52.222
Thus Carlton in Bedfordshire just wins by
about 2 minutes.
However, the true winner is likely to be a lost
Carlton in Carlford Hundred in Suffolk. Carlford Hundred lies completely
to the south of either Cartlon above. It is Calletuna (sic)
DB, Carletuna 1086 (c.1180) InqEl, probably Gilbertus de
Carleton 1327 SR. There is a caveat that it might be from a
personal name Karli. Cf. Anderson, English
hundred-names
i.92.
Keith