First, hats are just a sub set of head coverings—which come in lots of different styles—from symbolic and simple, to ornate and extensive.
And covering ones head, for functional reasons, or religious, or cultural reasons has a long and complex history (I have some links at the end to some histories of hats—I think they are inadequate, but a start in case you’d like to learn more!)
Hats can be functional—they can shade your head and keep it cooler, or insulate your head and keep it warmer, (see this post about conserving body heat—a warm hat makes a big difference!)
But hat have lots of other purposes besides these, and there are many conventions and rules (some of which we still adhere too, many of which have fallen by the wayside!)
Today, in US and most of western world, head covering are almost purely functional (warmth/shade) or decorative—be they Easter Sunday show off hats, or sport team caps.
We often forget the long history of hats, and of social conventions (now largely ignored) for covering ones head.
Religious groups of all stripes often have requirements for covering the head—by both men and women. The requirements are often different, but there are requirements for both sexes—and different rules for wearing (and removing!)
Hats and head coverings could (and sometimes still are) marks of status –one extreme is the crown or tiara—but it is also true that Queen Elizabeth is never with out a hat (a fancy hat—a reminder of crown she is title to)—and remove a hat can be a sign of subservience or humility.
In some cultures, religious riites require hats –in others, they require the removal! (and sometimes there are different rules for different members of the religious community! )—In most Christian churches, men’s heads are uncovered—but bishops and cardinals are exceptions.
A bishop and his miter –are as distinctive as a swami and his turban—in each case, the hat (or headgear) is a indication of status.
But, once, a fisherman hat, and newsboys hat, and widows cap, were also distinctive identifiers to classes, and social standing. A Fez was, for many years, a cultural hat that defined Turks—and is still worn despite laws prohibiting it!
In the court of Henry the Eight, Queen Katherine wore the peaked cap that was the style of the Spanish court—(and many woman of the English court copied her style.)
Anne Boleyn, who spent several years in the French court, wore the crescent moon shaped cap that was the style there, when she returned to England.
As their fortunes rose and fell—so did the styles of headwear in court.
Katherine could see Anne influence in court by looking at the styles worn in court!
Years later, Anne saw clearly her friends abandon her—and her crescent moon head dress!
50 years ago, Jacqueline Kennedy changed fashions with her classic pill box hats (and made wearing a square scarf (a kerchief) an acceptable head covering for church!)
Our language is full of hat and headgear idioms--
We “wear a feather in our cap”, or salute “hats off to you”, “throw our hat into the ring”, ‘tip our hats (to you)”, or “keep it under (y)our hat”—are just a few to come to mind—but there are many more.
So knit a hat—and think about all the history of headgear—and be part of the continuum.
One history of hats—(and there are many more, some more complete, some, well less complete)