DefinitionYan, a vassal state of Zhou in present-day Hebei and Liaoning; north Hebei; the four Yan kingdoms of the Sixteen Kingdoms, namely: Former Yan 前燕 (337-370), Later Yan 后燕 (384-409), Southern Yan 南燕 (398-410), Northern Yan 北燕 (409-436); surname Yan
