What is this bonnet/headgear called

[kingandrew]

As Steve notes, both the Basque beret and Scottish bonnets of various names are simple knit or felted caps, of a sort found in many cultures, as they are about the simplest head coverings to make. Of course, such items will evolve and get elaborated over time, as we can see with the selection of bonnets we have in Highland dress today(tams, balmorals, glengarries, and so on).

To add to Anne the Pleaters point, wool was the great cash crop and export of medieval Britain, much as oil is for today's Saudi Arabia. To help promote wool, a law was passed requiring all men in the kingdom to wear wool caps. Of course, given the chilly climate of the time and need to spend much of your day outdoors, I imagine most people would have been sporting whatever affordable and warm cap, hat, or hood they could find, regardless of statutes from king and parliament.

It is interesting to compare the actual images of 18th century bonnet from paintings with the costume designs for the Outlander TV show. Looking back on a romanticized past, the Victorians tended to imagine elaborate folk costumes, as we see illustrated in the complicated kilt outfits they show on ancient Celts in some history books from that era. Today, we seem to imagine people from any earlier period as hopelessly primitive compared to us. And certainly, the Highlands in the 1740s lacked many "modern conveniences" that we are accustomed to, as did every place in the world at that time. Yet people were well capable of clothing themselves in a functional manner. Anyone who looks at costume movies from the past will notice how 1970s the clothes in Robert Redford's Great Gatsby look, while De Caprio's Gatsby is dressed in the "skinny jeans" cut of the 2010s. So I guess we are always projecting our own expectations backward.

Andrew