One of the earliest known vegans was the Arab poet al-Maʿarri, famous for his poem “I No Longer Steal From Nature”. (c. 973 – c. 1057).
The first known vegan cookbook was Asenath Nicholson’s Kitchen Philosophy for Vegetarians, published in 1849
These are documented historical facts. Not “saying something” which ironically appears to be the position you are claiming.
Did the modern name come about in the 40’s? yes, that’s the etymology of it. But you’re treating that fact like the movement or ideology was formed at the same time, which is tremendously, provably wrong. It’s like claiming gay people are a relatively new invention because the term “homosexual” wasn’t coined until the 1890’s