These postcards, made year-round and bearing both holiday-related and more generic messages, were the work of local women. The small industry that sprang up around the cards was a way for French and Belgian citizens, many of whom were displaced from their homes during the war, to earn money doing portable piecework. Women would embroider a message or design on a strip of silk mesh or organza. The companies that mounted the finished strips on paper postcards churned the items out in factories. The Library of Birmingham estimates that, in total, around 10 million such cards were produced during the war.