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Code Girls -

Pictured: female US Army Signals Intelligence Service cryptologists at work in 1943 at Arlington Hall in Virginia. The more than 10,000 women who served as cryptographers (code makers) and cryptanalysts (code breakers) for the United States military during the Second World War were known as Code Girls.

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Code breakers -

Two Code Girls at Arlington Hall operate a machine that unscrambles messages in the Japanese "Purple" cipher. The machine's existence was one of the most closely guarded secrets of the war.

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Female cryptanalysts -

Meanwhile in England, about 8,000 women were employed at Bletchley Park, the government's top-secret site for British cryptanalysts. Pictured are two employees at the Colossus Mark 2 codebreaking computer.

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Cracking the cipher -

This photograph shows the machine room in hut 6 of Bletchley Park. The cryptographers deciphered top-secret communiques between Hitler and his armed forces. These communiques were encrypted in the Enigma code, which the Germans considered unbreakable but the codebreakers at Bletchley cracked with the help of 'Bombe' machines like Colossus, the world's first electronic programmable computer, which decoded the even more sophisticated Lorenz cipher, and so aided the Allies to victory.

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Women's Land Army -

Created in 1917, the Women's Land Army (WLA), a British civilian organization, placed women with farms that needed workers during the Great War, and again at the outbreak of the Second World War. The WLA became a symbol of the home front in Britain as men were called up to serve in the armed forces.

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Silver-brazer -

In the United States, women were trained to undertake vital labor, responsibilities that included silver-brazing cones for supercharger oil drain tubes of Wright Cyclone warplane engines. This photograph was taken at the Curtiss-Wright Corporation premises in New Jersey in the early 1940s.

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Powering the war effort -

A woman concentrates on her job working on an engine at the North American Aviation (NAA) plant in California. NAA designed and built some of the most iconic aircraft of the Second World War, including the P-51 Mustang fighter and the B-25 Mitchell bomber.

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"Riveting Rosies" -

An American female worker drives rivets into an aircraft while another sits in the cockpit checking they've been securely fastened. The women wear aprons and their hair is tucked into scarves. A woman who went to work in industries to aid the war effort and was assigned this particular role became affectionately known as Rosie the Riveter.

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Breaking down racial barriers -

The Second World War saw a great reduction in racial tension between American blacks and whites. Race discrimination was prohibited by law in the defense industry, and many African Americans worked side-by-side with whites in defense jobs. Pictured: African American women welders prepare to work on SS George Washington Carver docked at Richmond, California.

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Trackwomen -

Here, five African-American women pause for the camera in 1943 while working with the Baltimore & Ohio Railroad as trackwomen. They helped maintain and inspect railroad tracks.

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Dirty job -

Rarely did women employed in industry during the war mind getting their hands dirty. One of the grubbiest—and most dangerous—gigs was cleaning the tops of blast furnaces. This required the wearing of heavy overalls and gasmasks, as illustrated by these two women at a US Steel plant in Gary, Indiana.

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Star employee -

A female civil service worker at the Corpus Christi Naval Air Base in Texas puts the finishing touches to American insignia on the wing of a repaired US Navy aircraft.

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Patriotic duty -

An overtly patriotic task for American women was the sewing of the Stars and Stripes to be raised over US armed forces installations and on the battlefield.

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Red Cross nurses -

Red Cross nurses are seen here sewing dresses for children as part of the organization's war refugee relief program.

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Noor Inayat Khan (1914–1944) -

For a few select women, the Second World War was to test their courage and bravery to the very limit. Moscow-born Noor Inayat Khan worked for the British as a Special Operations Executive (SOE) agent. Operating under the codename Madeleine, she became the first female wireless operator to be sent from the UK into occupied France. She was betrayed and captured, and executed at Dachau concentration camp. Khan was posthumously awarded the George Cross for her service in the SOE, the highest civilian decoration for gallantry in the United Kingdom. 

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Violette Szabo (1921–1945) -

Similarly, Violette Szabo, a Paris-born British Special Operations Executive (SOE) agent, worked with the French resistance behind enemy lines. She too was eventually captured and ended up in Ravensbrück concentration camp in early 1945, where she was executed. Szabo was the second woman to be awarded the George Cross, bestowed posthumously.

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Women's Auxiliary Air Force -

A member of the Women's Auxiliary Air Force (WAAF)—the female auxiliary of the Royal Air Force during the Second World War—carries out electrical repairs in an armaments depot.

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Canadian Women's Army Corps -

The Canadian Women's Army Corps (CWAC), a non-combatant branch of the Canadian Army for women, was established in 1941. Here, a volunteer member of the corps models the new, all-weather CWAC uniform.

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High working standards -

During the war in factories all over Canada, thousands of women were employed in small arms ammunition production. Plant managers reported that in all operations where girls had replaced men, a high standard of workmanship had been maintained. This 1942 photograph shows a female worker loading a machine gun magazine.

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Quality control inspector -

A quality control inspector checks hundreds of Mk II Brodie helmets in a Canadian factory before the steel combat headgear is issued to combatants.

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At the lathe -

The war effort in the Soviet Union relied of hundreds of thousands of women to turn over production of key armament components and carry out repairs on damaged equipment. In this 1940 image, women handle lathes in a factory during the early stages of the conflict.

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Collective effort -

Elsewhere, women took to the vast steppes of the Russian countryside as collective farmers to replace men who had left for the front.

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Reich Labor Service -

In Nazi Germany, the ranks of the Reichsarbeitsdienst (RAD)—the Reich Labor Service—were swelled in the years leading up and during the war by the compulsory inclusion of women whose responsibility it was to provide support for the Wehrmacht armed forces. Here, female Reichsarbeitsdienst der weiblichen Jugend (RAD/wJ) members are seen at a Nuremberg rally in 1937.

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In the frame -

The German war effort saw women joining the production line in factories across the country. Aircraft manufacture was a priority industry, and here a female worker inspects an airframe during its construction.

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Nutritional scientist -

Women were often assigned tasks depending on their skillsets and level of education. This young women, pictured in 1942, is working in a German laboratory for nutritional science, where she's studying the physiological process of nutrition in relation to the well-being of troops in the field.

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Tram conductor -

On Germany's streets, women could be found carrying out duties on the public transport network such as this Berlin tram conductor, photographed at work in 1943.

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Uncustomary role -

On the other side of the world in Japan, customary female social roles conflicted with the requirements of conflict. In the early years of the war, Japanese women were relegated to various volunteer associations, which did not involve direct factory work. Later, however, as Japan's losses mounted, it became a requirement for women to take up manual employment in industry. In this image, women work on radios for military use.

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Australian Women's Land Army -

The Australian Women's Land Army was created in 1942 to combat rising labor shortages in the farming sector as the war progressed. Women toiled for long hours often under a hot sun to farm land and harvest crops.

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Gunning for victory -

Female employees at a government munitions factory in Footscray, Victoria, feed cartridges into machine gun belts. Ammunition of all kinds, from bullets to the largest shells and the heaviest bombs, were manufactured in Australia for use by Australian troops, and to be shipped to England for use against Germany and Italy.

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Postal worker -

In Britain, women continued to take on jobs normally reserved for men, one such role being postal workers. Here, a woman mail carrier on a  motorcycle prepares to deliver a letter on two wheels.

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Steaming ahead -

An American locomotive, one of the first batch to arrive in the United Kingdom for many years, is seen being cleaned by a team of women in 1943 before the giant engine is put into service. 

Sources: (The National WWII Museum) (The History Press) (Imperial War Museums) (Time)

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