Shibata Shōan served as a bushō during the Sengoku and Azuchi-Momoyama periods.  He was a retainer of the Ōtomo clan.  Shōan served as the lord of Asahidake Castle in the Amabe District of Bungo Province.

He adopted the name of Shōan after entering the priesthood and his real name is unknown.

Shōan was associated with a branch of the Shibata family descended from the Tachibana-Ōgawara clan.  His family were kokujin, or provincial landowners, in the Ōno District of Bungo (the Notsuin group) serving the Ōtomo clan.

Initially, Shōan was assigned to Asahidake Castle in Bungo on the border with Hyūga Province.  Around this time, in 1578, the Ōtomo were in the midst of a rapid decline owing to the loss of many capable retainers in the course of a major defeat at the Battle of Mimikawa.  Given these circumstances, the assignment to guard the provincial border was important, but Shōan viewed it as a demotion and was resentful, waiting for an opportunity to gain an advantage.  According to one historical account of Bungo and Satsuma, Shōan commented on the increasing responsibilities of his younger brother, Shibata Reinō, lamenting to a retainer named Hoashi Ichiyata “I am the head of the Shibata family in Bungo.  With the attention given to him by the governor-general, Reinō who is an illegitimate son, shows us contempt.  Reinō is even allowed to use the family crest of the Ōtomo and given free rein to do as he pleases.  We are treated as outsiders and always frustrated.  This resentment toward Reinō is nothing but resentment toward our lord.”  He is therefore surmised to have been very jealous of Reinō.  For his part, Reinō was known for his mastery of the spear and called the Hercules of Bungo.

In 1586, the Shimazu clan of Satsuma Province started the Hōsatsu War by invading Hyūga with an army commanded by Shimazu Iehisa.  Soon after the invasion, Shōan betrayed the Ōtomo but the Shimazu were suspicious of Shōan so they sent him to Amatsura Castle while his wife, children, and other family members were sent to Hoshikawa Castle.  Upon learning of the betrayal, the Ōtomo aimed to kill him and quckly dispatched Saeki Koresada to surround Hoshikawa Castle.

The betrayal of the Ōtomo clan was originally an individual decision by Shōan so a member of the castle garrison named Ashibetsu Daizen colluded.  As a result, Shōan’s entire family including wife and children were apprehended and forced to take their own lives at the Saeki-Saishō Temple.  Resentful that the Shimazu clan failed to dispatch reinforcements, Shōan rebelled and holed-up in Amatsura Castle but was then murdered amidst the chaos reigning among the garrison in the castle.