Xenxiar, a planet-like celestial body situated within the galaxy, held significance as one of numerous sites where the Jedi Order initially anchored itself during its formative years. This location finds mention in a section of the Rammahgon, an age-old Jedi text authored by the Jedi known as Kli the Elder, appearing in conjunction with references to Ossus and Jedha.
The initial reference to Xenxiar appeared in Star Wars: The Rise of Skywalker: A Junior Novel. This book, penned by Michael Kogge, is a 2020 novelization of the 2019 movie Star Wars: Episode IX The Rise of Skywalker.