Abstract: The newly unearthed epitaphs of Yuwen Quhuo, Yuwen Jingyi, Wang (wife of Yuwen Jun), Yuwen zhongkui, Yuwen Shiyuan, and Cui(wife of Yuwen Fu)—members of the Sui-Tang "Erwanghou"(二王后) Duke of Jie lineage-provide new evidence for the inheritance of the Duke of Jie. The inscriptions not only reveal the family's political connections with the Sui and Tang Dynasties but also reflect the evolution of the "Erwang and Sanke"(二王三恪) system. After the Sui Dynasty replaced the Northern Zhou, Emperor Jing of Zhou was enfeoffed as the Duke of Jie. Subsequently, most of the Northern Zhou royal family was exterminated, with only the collateral branch Yuwen Luo inheriting the dukedom. When the Tang succeeded the Sui, Li Yuan may have sought to deny the legitimacy of Yang Dong (of the Eastern Capital) and Yang Hao (of Jiangdu) by reappointing Yuwen Luo as the "Erwanghou", reaffirming the "Guanzhong-centric" tradition of the Zhou and Sui. The Duke of Jie title passed down to Yuwen Luo's grandson Yuwen Xian, who was deposed by Empress Wu Zetian. Consequently, when Yuwen Xian's son Quhuo wrote of his father's title in his epitaph, he used subtle wording to avoid explicit mention. After Wu Zetian returned power to the Tang, Emperor Zhongzong reappointed Xian's eldest son Lihuo as "Erwanghou". The title then passed to Lihuo's grandson Yuwen Yan, who was again abolished by Emperor Xuanzong but soon restored. During the An Lushan Rebellion, Yuwen Yan followed the Tang court, earning the favor of Emperor Suzong. After Yuwen Yan's son Zhongkui inherited the title, he moved to the suburbs and rarely visited Chang'an. Zhongkui's son Shiyuan waited several years, serving as a county magistrate and deputy before finally inheriting the title. Even Shiyuan's eldest grandson Yunkun fell to the position of a low-ranking official in a provincial government. Though the Duke of Jie family ranked among the first-class aristocracy, they possessed no real political advantages, serving merely as foils to the moral fortune and mandate of heaven of the Sui and Tang Dynasties.