What is "kuniumi"

In Japanese mythology, the is the traditional and legendary history of the emergence of the Japanese archipelago as narrated in the Kojiki and Nihon Shoki. According to this legend, after the creation of Heaven and Earth, the gods Izanagi and Izanami were given the task of forming a series of islands that would become what is now Japan. In Japanese mythology these islands make up the known world. The creation of Japan is followed by the creation of the gods ( kamiumi).