CROWN PRINCE KA OF ZHAO/CROWN PRINCE JIA OF ZHAO
Japanese Name: Crown Prince Ka of Zhao
Chinese Name: Crown Prince Jia of Zhao
2.Activities in History
Crown Prince Jia of Zhao is the oldest son of King Daoxiang of Zhao. He is said to be a better ruler than his younger brother, Prince Qian. However, King Daoxiang decided to strip the title of Crown Prince off Prince Jia and passed it to Prince Qian, which accelerated the demise of Zhao state.
After the fall of the Zhao capital of Handan, Prince Jia led the remnants of the Zhao eastward to build the state of Dai. Dai joined forces with Yan to defend against Qin but fell 6 years later to Qin’s almost unstoppable army.
Shi Ji–Annals of Qin Shi Huang：
十九年，王翦、羌瘣尽定取赵地东阳，得赵王。引兵欲攻燕，屯中山。秦王之邯郸，诸尝与王生赵时母家有仇怨， 皆坑之。秦王还，从太原、上郡归。始皇帝母太后崩。赵公子嘉率其宗数百人之代，自立为代王，东与燕合兵，军 上谷。大饥。
19th year(of Ying Zheng’s rule), Wang Jian and Qiang Lei captured Dongyang remaining and captured the king of Zhao. Their armies were then stationed at Zhongshan, all ready to attack Yan. King of Qin arrive in Handan(Kantan, capital of Zhao). He buried alive all of his mother’s enemies there. The king of Qin then returned, traveling across Taiyuan and Shang county. Prince Jia of Zhao led his clan of hundreds of men to the Dai region, proclaiming himself as the king of Dai, joining forces with Yan to the east and stationing their armies at Shanggu. A great famine occured.
25th year(of Ying Zheng’s rule), a huge army was deployed and led by Wang Ben to attack Liaodong region of Yan, capturing King Xi of Yan. He also attacked Dai, capturing King Jia of Dai.
Shi Ji–Aristocratic Family of Zhao：
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。
Words from the Grand Historian: I heard from Feng Wangsun that King Qian of Zhao’s mother is a courtesan liked by King Daoxiang. King Daoxiang stripped the title off his elder son Jia and made Qian the Crown Prince. Qian lacked the quality of a king, listened to bad advises, executed the excellent general Li Mu and trusted Guo Kai. This is ridiculous! After Qin captured Qian, the remnants of the Zhao royalty pushed Jia to become king. After ruling Dai for six years, the armies of Qin destroyed Jia’s army, annexing the entire Zhao
Sources: baike.baidu.com/item/史记·秦始皇本纪/ and baike.baidu.com/item/赵世家
3.Interesting facts and predictions
The quality of the Zhao ruler was the main reason for the fall of Zhao. After King Daoxiang died the same year as the year Qin captured Ye(Gyou), instead of his elder and supposedly more worthy son, Jia, ascending the throne, his less capable son, Qian became the new king. King Qian continued to employ Guo Kai as his prime minister, who was bribed by Wang Jian during the final Zhao war. This led to the execution of Li Mu and later the fall of Zhao. Zhao could have survived for a longer time if the more capable Prince Jia ascended the throne instead. Even though Prince Jia manage to proclaim himself king of Dai after the fall of Zhao, it was just too late and there was no way they can stop the rampaging Qin anymore.
In the manga, the current Crown Prince Ka seems to be the future ruler that Riboku put all his hopes in bringing Zhao to its former glory. Ka seems to be siding with Riboku as well. Knowing history, Ka will lose his title as Crown Prince and many predict that he willingly does so to protect Riboku from the wrath of his father after losing the battle of Gyou. Coincidentally, King DaoXiang will die the same year as the fall of Gyou.