"One of the longest wars in history was the Hundred Year War, fought between England and France in the fourteenth and fifteen centuries."
The way you presently have it written it is the subject, but in the original sentence "the Hundred Year War" is functioning as the predicate nominative. One is the simple subject. Of the longest wars modifies one. in history is a prepostional phrase modifying wars. Consequently, the full subject is One of the longest wars in history.Hi, elroy.
Why not "the Hundred Year's War"?
--> The Hundred Year's War was one of the longest wars in history.