Complex sentence: Agnatic seniority and the rota system has been used in several historical monarchies, for example in Kievan Rus' during the Rurikid Dynasty, implemented by Grand Prince Yaroslav I the Wise (1019--1054).
Split into simpler sentences: Agnatic seniority and the rota system has been used in several historical monarchies. In Kievan Rus' during the Rurikid Dynasty, it was implemented by Grand Prince Yaroslav I the Wise (1019--1054).