In addition to family history, I have been trying to find out about several towns in the British Isles that have Blakeney (with that spelling) as part of their name.
Here is what The Oxford Dictionary of English Placenames had to say about it:
Blakeney Gl(oucestershire) [Blachen', 1185, Blakeneia 1196 P],
Blakeney N(or)f(olk) [Blakenye 1242, Blakene 1248 Cl]
'Black Island' or Blacca's Island'. Blakeney in Norfolk was formerly known as Snitterley
However, in the past, they have been spelled differently. One that is currently spelled Blakeney, was spelled Blackney in c. 1564. This scan is part of a map that belonged to Sir William Cecil, who would later become an important figure in the government of Elizabeth I. The town can be seen on the coast near the middle of the image.