From Appalachian Magazine:

For my father and so many others, a pocketknife was an essential tool to their daily life.  The men who carry them are hardworking, do it yourselfers, who were raised to rely on themselves in nearly every situation.
The history of the pocketknife is quite telling, with its widespread usage dating back to the 1600s, where they were known as peasant knives and were used by the poorer working class of England.