A waistcoat, or vest as it is commonly referred to in North America, is a sleeveless article of clothing that is usually worn over a collared dress shirt and under a coat or jacket. It is typically paired with a tie and suspenders. The waistcoat is usually worn as part of a three-piece business suit, or as an element in men’s formalwear. Waistcoats can be single- or double-breasted, typically are made out of polyester, and usually have pockets in the front to hold various items, such as a pocket watch.
This garment was integrated into men’s everyday wear by King Charles II during the restoration of the British monarchy in the 17th century. While in modern times the waistcoat matches the whole suit, it was originally customary for the waistcoat’s color to contrast with the suit. This lasted until the mid-19th century, when Prince Albert began wearing restrictive waistcoats of muted colors that accentuated a man’s body as opposed to being a colorful focal point of the suit itself. Society followed Prince Albert’s lead, showing off silhouettes of broad shoulders and puffed-out chests, emphasized by the tight vest.
It is common for a gentleman to keep his bottom button unfastened — a custom that hails from King Edward VII of the late 19th and early 20th centuries. Also, it has been fabled that the king kept his last button open to keep his vest from riding up while he was atop a horse. It is more probable, however, that it was kept unbuttoned as a result of his swelling waistline. As King Edward VII was highly fashionable, his followers copied his look and kept their vests unbuttoned at the bottom, as well.
Structured similarly to a close-fitting jacket, the waistcoat buttons down the middle and can be either single-breasted or double-breasted. The vest is typically made from polyester or a similar material, and the fabric generally matches that of the pants and jacket when paired with a three-piece suit. Belts are not usually worn with a waistcoat, as suspenders are worn instead. Traditionally, gentlemen kept their pocket watches in the front waistcoat pocket with the chain strung through the buttonhole, although the pocket watch has since fallen behind in popularity due to the wristwatch.
World War II played a major part in the decreasing popularity of the vest. Due to fabric rationing during the war and the influx of a more casual daily appearance, people stopped purchasing waistcoats. In modern times, Americans see them as an accessory to a man's or woman's outfit as opposed to an integral element of a business suit. While still regarded as an appropriate piece of men’s formalwear in the United States (US), the vest is more often worn by conservative businessmen in other parts of the world.