D-Day and the Crowd

In 1943, the U.K. government broadcast a radio and print appeal to British citizens, urging them to send photographs, postcards, and images taken before the war depicting the coastline of continental Europe. Citizens responded—millions of photographs were mailed and delivered to the War Office.

INT researchers recently found this collection lying in thousands of boxes in one of the world’s great museums. The U.S. and U.K. governments used these images in war-planning for the June 1944 D-Day invasion. This documentary shows how, for “Operation Overlord,” hundreds of servicemen and servicewomen hand-coded and tagged these images with longitude and latitude and other geographical information, effectively taking millions of pieces of information crowd-sourced from the public and making them into critical intelligence that helped to turn the tide of the war.