Rosie famously riveted on the home front during World War II, but the fighting of World War I had likewise necessitated American women being recruited to replace men in the workforce. In this classic 1918 photo by Underwood & Underwood, young women operate the Waldorf-Astoria Hotel’s Stock Exchange Board, reading tickers and manually adjusting numbers. The Waldorf had several years earlier shown a progressive attitude toward women when it reportedly became the first upscale NYC hotel to allow women to stay in its rooms without an escort. Two years after this photo was taken, the Nineteenth Amendment was ratified, and U.S. women had won the vote.