The most reasonable answer to that question would be World War II due to the rationing of many fabrics and textiles.
World War II happened in the 1940's, and it was maddening indeed.
Fashion Forecast No- 6 - 1940 was released on: USA: 6 February 1940
Fashion Takes a Holiday - 1940 was released on: USA: 20 March 1940
fashion has changed since the 1940s because ideas and inspirations has changed. What was "in" in the 1940's is not what the 2008 fashion generation has to offer
The cast of Fashion Takes a Holiday - 1940 includes: Jim Bannon as Narrator
The cast of Fashion Forecast No. 6 - 1940 includes: Ilka Chase as Narrator
Fashion Forecast No- 6 - 1940 is rated/received certificates of: USA:Approved USA:Passed (National Board of Review)
One major event that happened on May 14, 1940 was that the Netherlands surrendered to the German forces during World War Two.
World War II was one American event that happened in September of 1940. Also, the Great Depression was coming to an end during this month and time frame.
The war decided what was in fashion, because of all the rationing, there were only certain styles and materials allowed.
World War two was the event that really changed fashion. Most materials were needed for the war effort so fashion had to use new or unusual materials to create clothing and accessories. For example wool was rationed so clothing was made of Rayon (a new invention) and America cotton. Shoes were made of velvet, mesh, and reptile skins since leather was unavailable. Rationing made what was available even more limited. You couldn't sew outside pockets, add pleats, or other decations made of fabric because these wasted fabric. Many women re purposed old clothing and made new clothing out of it. Styles had to be simple and easy to make for the home sewer. I could go on and on. I just completed a book about 1940's fashion with a lot of information about how the war effected fashion. Search for 1940's Style Guide ebook and you can read more about it.
The population of the United Kingdom in 1940 was approximately 47 million people. This figure reflects a period during World War II, which significantly impacted demographics and migration patterns. The population was influenced by factors such as wartime casualties and changes in birth rates.