How did cotton win over linen anyway?
In short, colonialism, slavery and the industrial revolution. In length:
Cotton doesn't grow in Europe so before the Modern Era, cotton was rare and used in small quantities for specific purposes (lining doublets for example). The thing with cotton is, that's it can be printed with dye very easily. The colors are bright and they don't fade easily. With wool and silk fabrics, which were the more traditional fabrics for outer wear in Europe (silk for upper classes of course), patterns usually needed to be embroidered or woven to the cloth to last, which was very expensive. Wool is extremely hard to print to anything detailed that would stay even with modern technology. Silk can be printed easily today with screen printing, but before late 18th century the technique wasn't known in western world (it was invented in China a millenium ago) and the available methods didn't yeld good results.
So when in the late 17th century European trading companies were establishing trading posts in India, a huge producer of cotton fabrics, suddenly cotton was much more available in Europe. Indian calico cotton, which was sturdy and cheap and was painted or printed with colorful and intricate floral patters, chintz, especially caught on and became very fashionable. The popular Orientalism of the time also contributed to it becoming fasionable, chintz was seen as "exotic" and therefore appealing.
Here's a typical calico jacket from late 18th century. The ones in European markets often had white background, but red background was also fairly common.
The problem with this was that this was not great for the business of the European fabric producers, especially silk producers in France and wool producers in England, who before were dominating the European textile market and didn't like that they now had competition. So European countries imposed trade restrictions for Indian cotton, England banning cotton almost fully in 1721. Since the introduction of Indian cottons, there had been attempts to recreate it in Europe with little success. They didn't have nearly advanced enough fabric printing and cotton weaving techniques to match the level of Indian calico. Cotton trade with India didn't end though. The European trading companies would export Indian cottons to West African market to fund the trans-Atlantic slave trade that was growing quickly. European cottons were also imported to Africa. At first they didn't have great demand as they were so lacking compared to Indian cotton, but by the mid 1700s quality of English cotton had improved enough to be competitive.
Inventions in industrial textile machinery, specifically spinning jenny in 1780s and water frame in 1770s, would finally give England the advantages they needed to conquer the cotton market. These inventions allowed producing very cheap but good quality cotton and fabric printing, which would finally produce decent imitations of Indian calico in large quantities. Around the same time in mid 1700s, The East Indian Company had taken over Bengal and soon following most of the Indian sub-continent, effectively putting it under British colonial rule (but with a corporate rule dystopian twist). So when industrialized English cotton took over the market, The East India Company would suppress Indian textile industry to utilize Indian raw cotton production for English textile industry and then import cotton textiles back to India. In 1750s India's exports were mainly fine cotton and silk, but during the next century Indian export would become mostly raw materials. They effectively de-industrialized India to industrialize England further.
India, most notably Bengal area, had been an international textile hub for millennia, producing the finest cottons and silks with extremely advance techniques. Loosing cotton textile industry devastated Indian local economies and eradicated many traditional textile craft skills. Perhaps the most glaring example is that of Dhaka muslin. Named after the city in Bengal it was produced in, it was extremely fine and thin cotton requiring very complicated and time consuming spinning process, painstakingly meticulous hand-weaving process and a very specific breed of cotton. It was basically transparent as seen depicted in this Mughal painting from early 17th century.
It was used by e.g. the ancient Greeks, Mughal emperors and, while the methods and it's production was systematically being destroyed by the British to squash competition, it became super fashionable in Europe. It was extremely expensive, even more so than silk, which is probably why it became so popular among the rich. In 1780s Marie Antoinette famously and scandalously wore chemise a la reine made from multiple layers of Dhaka muslin. In 1790s, when the empire silhouette took over, it became even more popular, continuing to the very early 1800s, till Dhaka muslin production fully collapsed and the knowledge and skill to produce it were lost. But earlier this year, after years lasting research to revive the Dhaka muslin funded by Bangladeshi government, they actually recreated it after finding the right right cotton plant and gathering spinners and weavers skilled in traditional craft to train with it. (It's super cool and I'm making a whole post about it (it has been in the making for months now) so I won't extend this post more.)
Marie Antoinette in the famous painting with wearing Dhaka muslin in 1783, and empress Joséphine Bonaparte in 1801 also wearing Dhaka muslin.
While the trans-Atlantic slave trade was partly funded by the cotton trade and industrial English cotton, the slave trade would also be used to bolster the emerging English cotton industry by forcing African slaves to work in the cotton plantations of Southern US. This produced even more (and cheaper (again slave labor)) raw material, which allowed the quick upward scaling of the cotton factories in Britain. Cotton was what really kicked off the industrial revolution, and it started in England, because they colonized their biggest competitor India and therefore were able to take hold of the whole cotton market and fund rapid industrialization.
Eventually the availability of cotton, increase in ready-made clothing and the luxurious reputation of cotton lead to cotton underwear replacing linen underwear (and eventually sheets) (the far superior option for the reasons I talked about here) in early Victorian Era. Before Victorian era underwear was very practical, just simple rectangles and triangles sewn together. It was just meant to protect the outer clothing and the skin, and it wasn't seen anyway, so why put the relatively scarce resources into making it pretty? Well, by the mid 1800s England was basically fully industrialized and resource were not scarce anymore. Middle class was increasing during the Victorian Era and, after the hard won battles of the workers movement, the conditions of workers was improving a bit. That combined with decrease in prices of clothing, most people were able to partake in fashion. This of course led to the upper classes finding new ways to separate themselves from lower classes. One of these things was getting fancy underwear. Fine cotton kept the fancy reputation it had gained first as an exotic new commodity in late 17th century and then in Regency Era as the extremely expensive fabric of queens and empresses. Cotton also is softer than linen, and therefore was seen as more luxurious against skin. So cotton shifts became the fancier shifts. At the same time cotton drawers were becoming common additional underwear for women.
It wouldn't stay as an upper class thing, because as said cotton was cheap and available. Ready-made clothing also helped spread the fancier cotton underwear, as then you could buy fairly cheaply pretty underwear and you didn't even have to put extra effort into it's decoration. At the same time cotton industry was massive and powerful and very much eager to promote cotton underwear as it would make a very steady and long lasting demand for cotton.
In conclusion, cotton has a dark and bloody history and it didn't become the standard underwear fabric for very good reasons.
Here's couple of excellent sources regarding the history of cotton industry:
The European Response to Indian Cottons, Prasannan Parthasarathi
INDIAN COTTON MILLS AND THE BRITISH ECONOMIC POLICY, 1854-1894, Rajib Lochan Sahoo
Fabric types and summer heat
The world is seeing record temperatures again. A lot of people find little comfort in their summer wardrobe these days, so it's important to be aware of how fabric types can influence your well-being in hot weather.
The following list of fabrics is by no means exhaustive, but it covers the basics.
Some of the fabrics mentioned below are expensive when bought new. You'll often find them for cheap in second-hand shops and on thrifting platforms though. I'm literally wearing a €5 linen underskirt, a €1 silk top, and a €7 silk summer dress right now, just to give an example.
If you don't know where to start, try to stick to light-weight fabrics made of natural fibres. Look for light colours and open weaves.
You might be tempted to cover as little skin as possible in order to keep cool, but this leaves your skin vulnerable to sunburn. A thin layer of linen will often be more efficient at keeping you cool than leaving your skin bare.
Don't forget to wear sunscreen! Even if your skin type doesn't burn easily, it will still lower your chances of skin cancer. Look into sunscreens for children if you have sensory issues: they tend to be more sensory-friendly.
(Image source 1) [ID 1: a gray linen fabric with a tight weave.] / (Image source 2) [ID 2: a gray linen fabric with a loose weave.]
Polyester (to avoid):
Are your summer clothes making you ridiculously sweaty? Check the tag: you're probably wearing polyester.
Polyester is a synthetic fabric derived from petroleum: it's basically a plastic. It's strong, cheap, and stain resistant, which makes it a popular fabric. Even though a lot of summer clothes are made out of polyester, it's one of the worst fabrics to wear in summer.
Polyester is neither absorbent nor breathable, and captures heat. It traps sweat between your skin and your clothes, and it won't let you cool down. This leaves you feeling sticky and overheated. It can also cause static cling, which can be uncomfortable.
Not all synthetic fabrics are bad in summer: a lot of UV-blocking clothes are made of synthetics for example and can be a real life saver if you're sensitive to the sun. Try to avoid polyester if you can, though.
(Image source) [ID: close-up on a blue tightly woven polyester fabric that folds into a swirl at its centre.]
Cotton is a natural fibre that makes for a soft, durable, and breathable fabric. It allows air to circulate around your body which helps to keep you cool and get rid of sweat. It's a good basic choice.
Cotton has one downside: it's very absorbent, but takes a while to dry. If the weather's making you sweat excessively, the sweat can pool into the fabric of your cotton clothes. This will make them wet, resulting in visible sweat stains that can feel uncomfortable and will take a long time to dry.
If you can't stand how cotton feels, check out chambray weaves or bamboo textiles. They have similar properties to plain-weave cotton, but tend to be more sensory-friendly.
(Image source) [ID: close-up on a faded yellow tightly woven cotton fabric that folds into a swirl at its centre.]
Linen is the absolute king of hot weather fabrics. It's strong, absorbent, dries quickly, and is very breathable. It cools you down, but won't make you feel sticky because any sweat it absorbs will evaporate fast.
I frequently layer multiple thin loose-fitting linen garments when it's hot. Loose layers allow for air to circulate between your clothes while protecting your skin from the sun. It almost functions as a wearable air-conditioner.
Note that linen is prone to wrinkling. If this bothers you, know that linen requires extra effort during laundry to avoid this.
(Image source) [ID: close-up on a gray woven linen fabric that folds into a swirl at its centre.]
Silk is yet another natural fibre that makes for a strong, quick-drying, and pretty breathable fabric. It's soft and cool to the touch, which makes it a great sensory choice.
Silk is not as breathable as cotton or linen, but dries very quickly. This means it might make you sweat more than cotton or linen does, but once the fabric's moist it will dry faster.
Note that sweat stains on silk tend to be pretty visible. Silk's also prone to static cling.
(Image source) [ID: close-up on a light brown tightly woven silk fabric that folds into a swirl at its centre.]