The name Gunstead comes from the name Gunderstad. The norwegian family name Gunderstad is cinsidered by scholars to be of habitation origin. This term refers to surnames whose origin lies in the place recidence of the initial bearer. In this particular instance, the name is derived from Old Norse personal name Gunndr which is combined with the locative element "stad", "stedt", meaning "homestead". Variants of the surname Gunderstad include Gunnerstedt.
Norway along with Denmark and Sweden, did not establish fixed hereditary family names amongst general populace until quite recently. Traditionally, Norwegians have distinguished between persons bearing the same first name by attaching the name of the father to a persons forename, suffixed by "en" ("son of") or "datter" ("daughter of"). Island is a very good example of this. When a profusin of family names ending in "sen" had accumulated in Norway, it was obvious that new kinds of names wherere necessary. Therefore, within the last two centuries, Norwegians have often chosen the name of their ancestral farm or of their home town as a surname. One of the earliest references to this name or to a variant is a record of one Catharina Elisabeth Gunnerstedt who married Peter Norling in Søderbanke, Kopparberg, Sweden, on the 19th of April 1813. Additional references include the marriage of Sara Lena Gunnerstedt and Eric Semstrøm in Søderbanke, on the 24th of June 1819.
Additional information of the name is that it derives from Gunnrs-Tun, a viking pre 8th century personal name meaning Battle and Tun meaning Farm. The first recorded spelling is Bartholamew de Guneton in 1195.
This could be why the name has originated from two places without any connection to eachother.