When was Roman Catholicism invented?

I'd date it from the time Pope Leo I persuaded Attila the Hun not to sack Rome, in 452 AD. Attila died within a year from a nosebleed (!) and so he never did get to sack Rome, and the Pope's reputation grew. The West Roman Empire finally collapsed about 20 years later, so again the Pope's stature grew. The word "catholic" though was used earlier back in the previous century and maybe earlier, and signified belong to a common set of christian beliefs. But the Pope became a sort of de facto "primus inter pares" in the old Western side of the Roman dominion.