... is an oxymoron. That combination of terms gets used regularly and is just accepted without question. It's wrong. Heathen are pagans, typically Nordic. They are not "godless" and they are not "atheist". They are a hotch-potch of religious traditions that can easily rival any of the Abrahamic ones for sheer stupidity.
From google define:heathen -
In its broadest definition, pagan [heathen] denotes all non-Abrahamic religions, that is to say it denotes all religions other than Judaism, Christianity, and Islam.
1. not adhering to an Abrahamic religion; pagan.
2. (by extension) uncultured; uncivilized; savage, philistine.
3. pertaining to currents of Germanic neo-paganism known as Heathenry.
(1) Literally means "heath-dweller", and refers to practitioners of the Norse pagan faith.
(2) One who does not acknowledge the God of Christianity and Judaism and Islam.
Originally people of the heath or moor. Originally, it was a Christian term to denigrate followers of the old, pre-Christian Religion. Followers of Asatru and other ancient reconstructed aboriginal religions have embraced the term.
Another name for Pagan. Many contemporary practitioners of Teutonic Nature religions prefer this term for themselves and their spirituality.