King Zhaoxiang of Qin
Because King Zhaoxiang had not yet legally come of age (traditionally at the age of 20), his mother, who was now known as Queen Dowager Xuan, became the regent. She was supported by her brothers, Wei Ran and Mi Rong (羋戎), as well as two other sons, Prince Yi (公子悝) and Prince Fu (公子巿), the four of them collectively known as the "Four Nobles" (四貴).
King Zhuangxiang of Qin
Yiren was born to Lord Anguo, the second son and heir apparent of King Zhaoxiang, and Lord Anguo's concubine Lady Xia. He was chosen to serve as a political hostage in the Kingdom of Zhao. In Handan (the capital of Zhao) he met a merchant, Lü Buwei, who saw Yiren as extraordinary and detected in him the potential to become the king of Qin in the future. Lü Buwei treated Yiren well and presented his concubine Lady Zhao to Yiren. Lady Zhao later bore Yiren a son, Ying Zheng.