Qiaopi is the name given in Chinese to letters written home by Chinese migrants to accompany remittances, in the 150 years starting in the 1820s. Qiaopi had numerous functions and dimensions, ranging from economic and social to cultural and political. In June 2013, the Qiaopi Project was officially registered under UNESCO's "Memory of the World" programme, set up in 1992 because of "a growing awareness of the parlous state of preservation of documentary...