(historical) Collective term for the five non-Han nomadic tribes that migrated into northern China during the Western Jin Dynasty, namely: 匈奴xiōngnú, 鲜卑xiānbēi, 羯jié, 氐dī, and 羌qiāng. They are primarily associated with the period of the 五胡十六国wǔhúshíliùguó.