A hatter.
A tailor or a seamstress but generally there is no name for someone who makes and sells clothes
It would be illogical to assume every person in the entire world wore hats during the 1920's. A lot of people did probably wear hats during this time period, but there are always black sheep.
They are called busbies.
Monks
a) It was the fashion to wear hats b) They keep the head warm
Milliner
A milliner
A milliner is a person who makes hats.
A milliner.
A person who makes and sells lady's hats in called a milliner.
A haberdasher is a person who sells men's hats.
a bag maker just like a hat maker i guess I do think you are right, no specific name, that I can find, for a maker of bags, however someone who makes hats is called a "milliner" if they make women's hats, a "hatter" if the make men's hats or more generally "Modiste" which can mean someone who makes hats and someone who makes garments.
A hatter is a person who makes and sells hats.
a milliner is a person who makes hats
A milliner is a person who makes women's hats.
One who makes hats can be called a hatter or a milliner.
a Modist