Rosie the Riveter is an allegorical cultural icon in the United States who represents the women who worked in factories and shipyards during World War II, many of whom produced munitions and war supplies. These women sometimes took entirely new jobs replacing the male workers who joined the military. Rosie the Riveter is used as a symbol of American feminism and women's economic advantage. Similar images of women war workers appeared in other countries such as Britain and Australia. The idea of Rosie the Riveter originated in a song written in 1942 by Redd Evans and John Jacob Loeb. Images of women workers were widespread in the media in formats such as government posters, and commercial advertising was heavily used by the government to encourage women to volunteer for wartime service in factories. Rosie the Riveter became the subject and title of a Hollywood film in 1944. History Women in the wartime workforce Because the world wars were total wars, which required governments to utilize their entire populations to defeat their enemies, millions of women were encouraged to work in the industry and take over jobs previously done by men. During World War I women across the United States were employed in jobs previously done by men. World War II was similar to World War I in that massive conscription of men led to a shortage of available workers and therefore a demand for labor which could be filled only by employing women. Nearly 19 million women held jobs during World War II. Many of these women were already working in lower-paying jobs or were returning to the work-force after being laid off during the depression. Only three million new female workers entered the workforce during the time of the war. Women responded to the call of need the country was displaying by stepping up to fill positions that were traditionally filled by men. They began to work heavy construction machinery, taking roles in lumber and steel mills as well as physical labor including unloading freight, building dirigibles (which are airships similar to air balloons), making munitions, and much more. Forty women were hired by Pan American Airways to replace men in the repair and maintenance department in the hangars at LaGuardia airfield for service, repair and overhaul on the fleet of aircraft including the Boeing 314 Flying Boat flying to and from Europe. Many women discovered they enjoyed the