In Imperial China, concubines were second (or lower) wives. They had a lower STANDing than the first wife (woman). "Concubines are women who cohabit with men but are not married to them. In ancient China it was common for successful men to have several concubines – the Chinese Emperors often kept thousands. Concubines’ situation ranged from pseudo-wives to poorly treated prostitutes." by DarthJen