The ponytail can be found on men in business suits.
The Kingdom of Sweden has a minister of finance with a pony tail, Anders Borg.
I found this on Wikipedia:
"In the second half of the 18th century, most men in Europe wore their hair long and tied back into what we would now describe as a ponytail.
It was a mandatory hairstyle for men in all European armies until the early 1800s, after most civilians had stopped wearing ponytails."