(The name has been spelled many ways, it is also seen as: Gorkum, Gorckum, Gorgum)
Corkum is a derivative of the geographical place name "Gorinchem" (pronounced "Gorkum") a city which was/is located in Zuid Holland, in what is now the Netherlands.
Because the name is based on a location, there can be a number of families that have the same surname, but are completely unrelated to one another, except for having originally come from that same location. In fact there are a number of van Gorkum families that originated in the town of Gorinchem who emigrated to other towns in Holland ("van" meaning "from").
The pre-name "von" (the German equivalent of "van") was first applied to a person who had emigrated from the town of Gorinchem and was now living in Germany… hence "von Gorkum". This was the name that had initially been associated with the family of one Johannes whose son Peter Heinrich had emigrated from Gorinchem and in 1572 arrived in Wesel, United Duchies of Jülich-Cleves-Berg (now in Germany). There Peter Heinrich became known as Peter Heinrich von Gorinchem. His son, born in Wesel in 1600 and also named Peter Heinrich, was the first of our family to be born a von Gorkum, and also appears to be the first of the family to use the simpler phonetic spelling, "von Gorkum" (or von Gorckum).
By 1713, with the birth of Johann Wilhelm, the immigrant to Nova Scotia, the had family dropped the pre-name "von", and prior to their emigration the name was recorded as simply "Gorckum" or "Gorkum". The "Gorckum" spelling is the one used on the lists of passengers on The Pearl, the ship on which the family arrived in the New World at Halifax, Nova Scotia in 1752.
Some of the earlier official records for the province of Nova Scotia counties use the spelling of Gorgum (Chester Township Book). By the mid-1800s, if not sooner, the family name in Scot’s Bay had evolved into Corkum.
The links above on the left will direct you to the person pages of the members of our Corkum Family, but a reasonable starting point would be with Laurence Irvin Corkum, maternal grandfather of The 3 Tracys born c. 1975.