 Mainly aged between 20 and 35 and hailing from the northern Chinese provinces of Hebei, Jiangsu and particularly Shandong, as well as Wenzhou, they served as labour in the rear echelons or helped build munitions depots, repair railways and roads, and unloaded ships at Allied ports.Some worked in armaments factories, others in naval shipyards, for a pittance of three to five francs a day.At the time they were seen just as cheap labour, not even allowed out of camp to fraternise locally, dismissed as mere coolies.