AnswerA couple of changes in fashion were:
One was the peekaboo hair style popular among women at the wars outset, due to women following the amazing Hollywood movie star styles.
Due to so many women being called to industrial occupations in war industries, it was requested that Hollywood stars change their styles and encourage American women to wear their hair shorter and up, this deemed necessary for safety sake when operating machinery. The request was successful.
Also, to save cloth for the war effort, dresses were made shorter. They never reached anywhere near the high hem levels of 'minis' found in the 1960's however. But the 2 piece bikini was established during this time.
Otherwise there was not a lot of thought given to fashion during the war. Most peoples' efforts went towards more tangible and practical goals.
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In Britain of course, shortages and rationing slowed fashion development, and one effect of the War was the Austerity that followed it, not really lifting until the late 1950s. From contemporary photographs it seems that men's fashions were the more conservative, with an almost uniform appearance of rather drab clothes and hair styles (mainly "short back & sides" - nearly military standard) for most men for many years.
It changed it by just like world war ,the money issues people had and how the dresses had got allot MORE expensive because of the war. People wanted money to improve their shops because they might of been destroyed during the war.
Women's fashion became less constricting because of the ease of movement required to work in factories, etc. (which the women were doing because the men were off at war)
because everyone died
Helmets became more popular
The 1940s
World War Two.
World War II & Communism
World war two had Adolf Hitler in charge and it was about 1940s and in world war 1 it was in the 1915s
World War 2
Until the early 1940s World War 1 was usually referred to as the Great War.
WORLD WAR II!
World War 2 was the principal thing that occurred in the 1940's
it didn't
Fashion changes all the time regardless of war .