The young priest Kukai made his perilous journey to China as a member of a Japanese diplomatic mission in 804. Records indicate that he was already a master at dealing with bureaucratic superiors, not only by securing a place on the mission in the first place, but by negotiating (in accomplished Chinese) admission to study esoteric Buddhism at the esteemed Ximingsi Temple in Xi'an (then known as Chang-An), the Tang Dynasty capital and gateway to the Silk Road.
There, Kukai (774-835, posthumously named Kobo Daishi) revealed a formidable intellect. Within two years -- instead of the 20 years originally planned -- he was initiated as a master with responsibility to spread The Teachings.
In 806, Kukai returned to face Japanese political and religious factions jostling for power -- a minefield he navigated with considerable skill. After a few years he received imperial permission to establish in Wakayama Prefecture a monastic retreat on Mount Koya, then a remote, forested wilderness, several days' walk and climb from the old capital, Kyoto.