The Fiske Roots and Origin
It's only within the last couple of centuries that most people have been literate and able to spell their own name. Therefore, in centuries past Fisk was spelt with several variants including Fisc, Fiske and Ffiske.
Fiske is the word for fish in Old English (Anglo-Saxon), Norwegian, Swedish, Danish and Frisian. Frisia aka Friesland was inhabited by the tribe of Frisians in the 5th century who occupied the whole of the North Sea coastline from the Rhine to the Elbe e.g. coastal regions of southern Denmark, Germany and part of the Netherlands. Therefore it should be no surprise that their language would have some influence on the languages of neighbouring cultures trading with them e.g. the word for 'fish' in Norway, Sweden and Denmark.
The Frisians were Germanic in origin and spoke the same West Germanic language that that along with the Old Saxon language formed the basis for the Old English language that developed as a spoken language in England between the 5th and 12th century.
Fiske given as a surname is most likely to refer to the profession of fishing e.g. fisherman rather than to the word fish itself. It's likely the first Fiske settlers were part of the Viking invasion from Scandinavia around 800AD, and subsequently they settled in Suffolk; the original spelling most likely to have been Fisc.
The name Fisc appears in the Doomsday Book on 1086 in Laxefelda, Suffolk, now known as Laxfield.