If you watch Turner Classic Movies, you might notice that everybody in any film made before 1965 seems to be wearing a hat whenever out-of-doors. Time was, in Europe and the U.S., nobody ever went outside, in any weather, without a hat. One would have appeared half-dressed. Ladies could even wear hats indoors, and many did. That is no longer the case. It seems people wear hats nowadays only to keep the cold out, or on special, festive occasions. Otherwise, a hat looks rather eccentric. What happened? How and why did hats pass out of fashion?
No cite while I’m at work, but I believe President Kennedy very seldom wore a hat, and this became the fashion – at least in the U.S. I suppose U.S. made movies might have exported the fashion.
Contributing factors to not wearing hats are modern climate controled buildings, better control of lice and other parasites, better hair products availible, hair styles that handle the weather better, less scalp deseases, and lastly fashion.
Screw hats, what happened to spats?!
Yeah, it’s almost like there was some groundswell of rebellion against established traditions in the early 60’s or something…
What do lice have to do with it? Hats don’t repel lice. Do they?
They keep them concealed, though. Or at least make a good effort.
I wonder if the advent of decent wet-weather clothes is relevant? After all, the classic image is of the man in the tricorn forging through the driving rain.
Nah, Kennedy was just following the trend. Hats were already on the way out by the time he was elected.
The hats we see men wearing up to ca. 1960 don’t seem to me to have much practical purpose. They don’t do much to keep your head warm or dry, and unless you wear them at all times they are not going to conceal head lice or other problems of cranial hygiene. No, I can only think that their ubiquity was down to simple fashion and conformity.
They help keep lice from transfering into long hair in public places. Think of those bonnets that covered womans hair, or those veiled hats that went to the shoulders. They were lice barriers.
It’s usually traced to Kennedy, as OldGuy says.
The story is that he didn’t wear a hat at his inaugural. Not quite true, as a zillion previous threads on this can probably be found. He didn’t wear the top hat during his inaugural address and it’s that image that people remember.
Still, the change was part of a much larger shift in styles toward casualness that was everywhere in society by 1961. Kennedy’s youth - his thick hair usually hatless and a contrast to Eisenhower’s baldness and general old guy image (sorry) - was a factor, but it would have happened anyway. Hats simply went out of fashion around then.
I wear my classic style black fur-felt Fedora when it’s cold or raining.
Of course, I also wear a totally rad Matrix-style black leather trench to go with it. So I don’t conjure up images of 1940s Irish mobsters.
Neil Steinberg, Hatless Jack: The President, the Fedora, and the History of American Style
And what is that unexpected inspiration? Read the book!
My vote is the overall trend towards more casual dress for males in the workplace, at home, and when they going out. I am guessing a pork-pie hat wouldn’t look so good with the clothes the average American guy wears 90% of the time (shorts, jeans, khakis, t-shirts, polo shirts and oxfords). A baseball cap or a beanie ski cap looks OK.
For all the poor suckas who have to wear suit and ties more often than just to weddings and funerals: maybe you guys can bring the classic hat back in style! 
There were a lot of radical cultural changes in the US after WWII. Radical enough that there is a pretty distinct divide between pre-war culture and post-war culture. From watching a century’s worth of movies, it’s my overall impression that hats were just one of the many things that were seen to be part of the older generation; the pre-war generation. They gradually just came to be seen as “square,” as the newly cosmopolitan war generation gave way to the baby boom generation. Like rock-n-roll gradually pushed jazz aside, hatlessness gradually did the same thing to the fashion of wearing hats.
That’s casual dress today. Hats fell out of favor with men in suits in the 1960s.
No explanation of why hats were seen to be part of the older generation. As I say above, hats fell out of favor with businessmen in the 1960s, not just the younger generation.
Because they were. It’s as simple as that.
Mildred: What’re you rebelling against, Johnny?
Johnny: Whaddya got?
All the explanation you’ll ever need, or get.
Hats didn’t go out of fashion. Hair came into fashion. Specifically, men’s hair grew longer. How can you show off your magnificent locks with a hat on?
By 1959, the decline of hats was well underway, but the “lower, longer, wider” trend in new cars probably contributed to it. A man no longer had enough headroom to wear a fedora while driving. By JFK’s time, the deed was done. As you can see at Snopes, he did wear a hat at his inauguration, but not often after that.
‘The wet-head is dead! Long live the Dry Look. From Gillette.’