Zhou Youwang 周幽王 (r. 781-771), King You of Zhou, was the last ruler of the Western Zhou period 西周 (11th cent.-770 BCE). His personal name was Ji Gongnie 姬宮湼 (also written Sheng 涅 or Huang 湟), and he was the son of King Xuan 周宣王 (r. 827-782).
According to historiography, King You did not care for government himself but entrusted politics to Guo Shifu 虢石父, who exploited the people in a cruel way.
He failed miserably during the campaigns against the Rong barbarians of Liuji 六濟戎. Several earthquakes and droughts worsened the general economic situation of the kingdom.
King You was a slave to his consort Bao Si 褒姒, and degradedQueen Shen 申后 and her son, in order to promote Bao Si and her son Bofu 伯服 to the position of queen, resp. heir apparent. Bao Si incited the king to cruelly punish his ministers and the lords.
Marquis Shen 申侯, father of the Queen, provided shelter to his grandson, the original heir apparent, and created an alliance with the Quanrong 犬戎 barbarians. In the battle of Lishan 驪山, the barbarians defeated the royal army, and King You was killed.
His heir apparent would take over regency as King Ping 周平王 (r. 770-720). King Ping moved the seat of government to the secondary, eastern capital of Luoyi 雒邑 (modern Luoyang 洛陽, Henan). He was the first ruler of the so-called Eastern Zhou period 東周 (770-221 BCE).