According to the Book of Mormon, Mosiah II, (/moʊˈsaɪ.ə/ or /moʊˈzaɪ.ə/) King Benjamin's son and Mosiah I's grandson, was king of the Nephite nation from about 124 BC to 91 BC. The Book of Mosiah is named after Mosiah II.
Accounts
Mosiah instituted a new governing system after all of his sons declined to succeed him as king, choosing rather to preach the gospel. This new government was based on judges elected and chosen by the people. After Mosiah's death in approximately 91 BC, this council of elected judges constituted the government of the land until Christ visited the Nephite nation (see Mosiah 29).
References
King Mosiah II Wikipedia(Text) CC BY-SA