IIRC, Stephen King's "The Running Man" and "The Long Walk" predate both Battle Royale and Hunger Games and deal with similar themes.
The story is similar to a Robert Sheckley's short story from 1952,"The Prize of Peril" adapted into a movie in Germany in 1970 "Das Millionenspiel" and in France in 1982 "Le prix du danger" (same year as King's Running Man novel)
I would say "The Prize of Peril" is the grandfather of these books, movies and series, as far as I know. Battle Royale is the start of another branch, though : it's not one vs many anymore, it's many vs many.