Originally Posted by
EasternTraveler
I have never been on an international Delta flight with a "First Class", but I have been on many with Business as the front of the plane. It was the lie flat seats in business.
Before business class became a thing in the late 70s, there was just first class and tourist/coach/economy class for the most part. Towards the mid-80s, a lot of airlines, including Delta, phased out first-class, but a lot didn't. In any event, DeltaOne is most certainly marketed and sold as business class.