周平王 / King Ping of Zhou
周平王 / King Ping of Zhou appears in 《资治通鉴·周纪》10丨 以家族单位 有蚂蚁吃大象的精神(1) through the episode’s account of 秦国 becoming a recognized state. The source says 秦襄公 escorts him east, after which Zhou Ping Wang grants Qin vassal status and land west of Qishan.
The grant matters because the episode says Qin still had to recover that land from the Quanrong. Qin’s recognition by 周王室 therefore becomes both a legitimacy claim and a territorial assignment.