Until the internet age? Hmmm, I think English overtook French a little before then. I’d put it somewhere between 1950 and 1970.
we in the anglophone world don't have a good idea of the other language traditions. What I mean by English not overtaking French is that before the internet age in much of the world French was considered hte language of culture, so, say, Poles learnt French, even though that had no "use" per se except to be cultured.
But with the internet age, there was a larger world and reason to learn English as the language of commerce.
I don't mean that the internet was the only reason, I dare say globalization at the same time played a role, i'm just calling it the internet age for want of any other term