Wada Michioki served as a bushō during the Sengoku period. He was a retainer of the Kōno clan and served as the lord of Iwagara Castle on a mountaintop near Tōon in Iyo Province.
In connection with a dispute among retainers of the Kōno clan, Kurokawa Michitoshi, the lord of Tsurugiyama Castle was killed by Kainō Michiyuki, the lord of Kotegataki Castle. This caused Michitoshi’s son, Kurokawa Michitaka, to resent Michiyuki. Later, Michitaka joined forces with Ōno Toshinobu, the lord of Ōyoke Castle, to attack Michiyuki, but Michioki provided support to Michiyuki, so Michitaka’s assault on the castle failed.
In 1554, after expanding his power, Michioki ceased to obey Kōno Michinobu (Sakyō-no-taifu), the head of the Kōno clan, so Michinobu ordered Hiraoka Fusazane, the lord of 棚居 Castle, to attack Michioki at Iwagara Castle. After the fall of the castle, Michioki fled into the mountains and took his own life. These events are recorded in a letter from Murakami Yoshitsugu (a retainer of the Kurushima clan) sent to a temple on Mount Kōya.
Later, a family member named Wada Michikatsu was called upon and granted Iwagara Castle by Michinobu.