I saw a rather faded print of a painting by Frank Moss Bennett: https://en.wikipedia.org/wiki/Frank_Moss_Bennett It showed a historical scene with all the men wearing heels, as they might well have done at that time. The period he specialised in was the 1700s and 1800s, so rather after the Carolingian period mentioned by @Shyheels in another thread. I can't find an online reproduction of the print I saw, where the heels are more prominent and perhaps a little higher than in the example on Wikipedia.
Since FMB had clearly researched his period, I think we can believe his representations are accurate. They show that men's heels spanned several centuries, before dying out in late Georgian or Victorian times.