The general concept is much older than even Nietzsche. I would put it at least as far back as the account of Thrasymachus in Plato's Republic[1], a critique of Socrates' concept of justice:
I proclaim that justice is nothing else than the interest of the stronger
I proclaim that justice is nothing else than the interest of the stronger
[1] https://www.gutenberg.org/files/1497/1497-h/1497-h.htm