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King 幽繆 You Miu of Zhao (also known as King 遷 Qian of Zhao)/ King Yu Boku of Zhao (King Sen of Zhao)
Japanese/Chinese: 趙遷 (赵迁)
Japanese Pronunciation: Chou Sen
Chinese Pronunciation: Zhao Qian
2.Activities in History
Officially the last king of Zhao proper, perhaps more well known as the king who executed Li Mu. He was approximately 10 years old when he ascended the throne in 235 BC, a very difficult time for Zhao as it has been almost completely eclipsed by Qin. During his reign Qin frequently attack Zhao. It was our favorite antagonist that would come to the rescue. Qin made use of Guo Kai (that guy who also got Lian Po demoted) to sow discord between Li Mu and the king.
Shi Ji, book of Zhao aristocratic family
King Dao Xiang died, his son You Miu ascend the throne
King You Miu first year, castle Bai Ren (was built). Second year, Qin attacked castle Wu (Wu Cheng), General Hu Zhe came to defend the castle but was defeated and KIA.
Third year, Qin attacked Chi Li and Yi An but was repelled by Li Mu. Li Mu was made Lord Wu An for this. Forth Year, Qin attacked Fan Wu and again was stopped by Li Mu.
Fifth year, a great earthquake at Dai (and description where Dai is). Sixth year, great famine (not sure what the quote means)
Seventh year, Qin attacked Zhao, Great General Li Mu and General Sima Shang countered. Li Mu was executed and Sima Shang was demoted (thanks to Guo Kai). Zhao Cong and Qi General Yan Ju replace them. Zhao Cong was defeated, Yan Ju fleed. The king surrendered.
Eight year tenth month, Handan (the capital) was conquered.
3.Comments and stuff
Whether he was a good or bad ruler is difficult to say. We are talking about leaving the fate of a state to a very young person especially at a time where conflicts could come any time. There are not many great ruler ascended the throne at such a young age. The earthquake and famine made it worse. It was traditionally believed that natural disasters are sign of change in Heaven’s Mandate.
太史公曰：吾闻冯王孙曰：“赵王迁，其母倡也，嬖于悼襄王。悼襄王废适子嘉而立迁。迁素无行，信谗，故诛其 良将李牧，用郭开。”岂不缪哉！秦既虏迁，赵之亡大夫共立嘉为王，王代六岁，秦进兵破嘉，遂灭 赵以为郡。
Sima Qian (Tai Shi Gong is his title): The mother of King Qian of Zhao, Lady Chang was a favorite of King Dao Xiang. He made Qian his heir instead of Jia. Qian was not a right (choice). He believe in slander (from) Guo Kai who was bribed and executed Li Mu. (not sure what the four letters mean) Qin not only captured him but also Prince Jia who escaped to Dai to be a king. Qin would eventually defeat Jia and made Zhao a commandery.
Sima Qian himself pointed that it was a mistake that King Daoxiang appointed Qian as his successor instead of his older son Jia (迁素无行 Qian is not right). Jia is approximately 5 or 6 years older than Qian.
After Qin conquered Zhao, Zhao royal family was exiled to Fang Ling 房陵 (northwestern today Hubei). While Jia was sent to Tian Shui 天水 (in today Gansu) as emissary to the Xi Rong. Zhao Qian is ancestor of most people with surname Zhao through emperors of Song Dynasty.
In case you wonder, Zhao Yun was from southwestern Hebei. His descendants settled in Sichuan (蜀 Shu, as in Shu Han is ancient name of Sichuan province). Zhao Yun is more likely descendant of several hundred clan member who escaped together with Jia (Dai is located in southwestern Hebei).