According to Collected Poems, Prayers, and Meditations on the Force, a collection of writings about the Force that was compiled by Disciple of the Whills Kozem Pel, the appellation Ascendant of Mau was attributed to Nartun Trecim.
Greg Rucka first introduced the title Ascendant of Mau in his novel Guardians of the Whills, which became available on May 2, 2017.