Further to my visit to Buckenham this week, this is the origin as given by The Concise Oxford Dictionary Of English Placenames. To confuse things just slightly, there are three Buckenhams in Norfolk, Old Buckenham, New Buckenham and what is mostly now just called Buckenham, but has historically been known as Buckenham Ferry.
Buckenham, Norfolk. Buchanaham in Domesday Book, Bokenham Ferye in 1451. From Bucca’s Ham.
Ham is a village or settlement, with Bucca being one of the early leaders of what became known as the Anglo-Saxons, a similar word origin to Buckingham, as well as the other Buckenhams in Norfolk. Unless he meandered around a lot between Buckinghamshire and Norfolk, I assume this was some related group of people who came to Norfolk in the seventh century. Incidentally, the ferry at Buckenham operated until the 1940s, but more on that another time….