Written By: Eliza Berman

Two events define 1940s fashion more than any others. The first was the beginning of World War II, in 1939. The second was its end, six years and one day later. American trends in the decade can be distinctly divided into those influenced by the changes brought by war—in particular the rationing of materials and the increase in women’s participation in the workforce—and those inspired by the freedom of post-war peace.

By the end of 1942, materials like wool and nylon had joined sugar and coffee on the growing list of rationed goods. Leather shoes would follow suit the next year, and Americans were strongly urged to donate scrap metal to the war effort. As a result, the silhouettes de rigueur at the beginning of the decade were essentially frozen in time, and fashion entered a no-frills period. (Quite literally ruffles were among a list of details, including extra buttons and pockets, eliminated during times of austerity.)

As a growing number of women entered the workforce to fill posts vacated by men at war, the popularity of pants skyrocketed—in part because factory work required the range of motion afforded by trousers, in part because nylon had been diverted from the manufacturing of stockings to the creation of parachutes. Many women sported tailored suits with squared shoulders and narrow waists, sometimes repurposing the suits that languished in their husbands” closets. And simple styles ruled the day as European fashions ceased to be available stateside.

But the tide shifted following the war—not all at once, but gradually, as Paris resumed its place as the headquarters of couture and Christian Dior’s “New Look” reintroduced more traditionally feminine styles. Utility gave way to softness as square shoulders were rounded and slim skirts became fuller. And the late “40s introduced a newly defined segment of the population, and with it a whole new style icon: the teenager.

Liz Ronk edited this gallery for LIFE.com. Follow her on Twitter @lizabethronk.

1940s LIFE Fashion Cover

March 4, 1940 issue.

George Karger LIFE Magazine

1940s LIFE Fashion Cover

April 22, 1940 issue.

Peter Stackpole LIFE Magazine

1940s LIFE Fashion Cover

May 13, 1940 issue.

Alfred Eisenstaedt LIFE Magazine

1940s LIFE Fashion Cover

October 21, 1940 issue.

Gjon Mili LIFE Magazine

1940s LIFE Fashion Cover

January 13, 1941 issue

George Karger LIFE Magazine

1940s LIFE Fashion Cover

March 24, 1941 issue

Herbert Gehr LIFE Magazine

1940s LIFE Fashion Cover

April 7, 1941 issue.

Gjon Mili LIFE Magazine

1940s LIFE Fashion Cover

May 19, 1941 issue.

Herbert Gehr LIFE Magazine

1940s LIFE Fashion Cover

April 20, 1942 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

May 11, 1942 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

July 20, 1942 issue.

Walter Sanders LIFE Magazine

1940s LIFE Fashion Cover

August 24, 1942 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

October 5, 1942 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

November 16, 1942 issue.

Walter Sanders LIFE Magazine

1940s LIFE Fashion Cover

March 1, 1943 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

May 3, 1943 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

September 13, 1943 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

October 11, 1943 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

November 15, 1943 issue.

Walter Sanders LIFE Magazine

1940s LIFE Fashion Cover

December 6, 1943 issue.

Walter Sanders LIFE Magazine

1940s LIFE Fashion Cover

May 8, 1944 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

July 17, 1944 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

August 28, 1944 issue.

Zoltan S. Farkas LIFE Magazine

1940s LIFE Fashion Cover

October 9, 1944 issue.

George Karger LIFE Magazine

1940s LIFE Fashion Cover

January 8, 1945 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

February 19, 1945 issue.

Alfred Eisenstaedt LIFE Magazine

1940s LIFE Fashion Cover

July 9, 1945 issue.

Ewing Krainin LIFE Magazine

1940s LIFE Fashion Cover

October 15, 1945 issue.

Alfred Eisenstaedt LIFE Magazine

1940s LIFE Fashion Cover

November 19, 1945 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

December 10, 1945 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

January 14, 1946 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

April 15, 1946 issue.

Ralph Crane LIFE Magazine

1940s LIFE Fashion Cover

June 17, 1946 issue.

Lisa Larsen LIFE Magazine

1940s LIFE Fashion Cover

October 14, 1946 issue.

Ralph Crane LIFE Magazine

1940s LIFE Fashion Cover

November 18, 1946 issue.

Loomis Dean LIFE Magazine

1940s LIFE Fashion Cover

January 13, 1947 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

March 31, 1947 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

May 5, 1947 issue.

Andre De Dienes LIFE Magazine

1940s LIFE Fashion Cover

June 23, 1947 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

September 22, 1947 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

January 12, 1948 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

March 29, 1948 issue.

Sharland LIFE Magazine

1940s LIFE Fashion Cover

June 7, 1948 issue.

Lisa Larsen LIFE Magazine

1940s LIFE Fashion Cover

October 18, 1948 issue.

Gordon Parks LIFE Magazine

1940s LIFE Fashion Cover

November 29, 1948 issue.

Nina Leen LIFE Magazine

1940s LIFE Fashion Cover

January 17, 1949 issue.

Leonard McCombe LIFE Magazine

1940s LIFE Fashion Cover

April 25, 1949 issue.

Gordon Parks LIFE Magazine

1940s LIFE Fashion Cover

June 6, 1949 issue.

Lisa Larsen LIFE Magazine

1940s LIFE Fashion Cover

August 29, 1949 issue.

Philippe Halsman LIFE Magazine

1940s LIFE Fashion Cover

November 14, 1949 issue.

Arnold Newman LIFE Magazine

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