Lifespan: Kyōroku 2 (1529) to 6/6 of Tenshō 19 (1591)
Rank: bushō and daimyō
Lord: Bessho Nariharu → Bessho Yasuharu → Bessho Nagaharu → Toyotomi Hideyoshi
Father: Bessho Nariharu
Siblings: Yasuharu, Yoshichika, Shigemune, wife of Ōgo Sadanori
Wife: Daughter of Fukushima Masanobu
Children: Yoshiharu, Muneharu, Nobunori, Fukushima Masayuki, Fukushima Masanobu (adopte dby Fukushima Masanori)
Bessho Shigemune served as a bushō and daimyō for the Bessho clan in eastern Harima Province.
In 1568, Shigemune hurriedly joined along with other family members in support of Ashikaga Yoshiaki, the fifteenth lineal shōgun, when Yoshiaki marched to Kyōto under the protection of Oda Nobunaga. Shigemune led diplomatic efforts around the time that the Bessho clan chose to cooperate with Nobunaga. This, however, caused tension with his second eldest brother, Bessho Yoshichika, who did not willingly accept a congenial relationship with the Nobunaga or his senior commander, Hashiba Hideyoshi.
In 1570, Shigemune’s eldest brother, Bessho Yasuharu, died and was succeeded as head of the clan by Yasuharu’s eldest son, Bessho Nagaharu. Shigemune, together with Yoshichika, then served as assistants to Nagaharu. Once Nagaharu rebelled against the Oda, leading to the Battle of Miki Castle, Shigemune took an alternate path and became a rōnin, or wandering samurai.
In 1585, Hideyoshi awarded Shigemune control of Yagi Castle and a fief of 15,00 koku in Tajima Province. Thereafter, in 1586, Shigemune deployed as a retainer of Hideyoshi for the campaign to subjugate Kyūshū known as the Kyūshū heitei and, in 1590, a subsequent campaign against the Gohōjō clan in Sagami Province known as the Odawara seibatsu. Shigemune later retired to the city of Sakai.
Shigemune wed the younger sister of Fukushima Masanori, and his son, Masayuki, was adopted by Masanori as his designated heir, but later removed from the line of succession. His second son, Muneharu, served as a hatamoto for the Tokugawa clan in the Edo period, dying in the Battle of the Tennō Temple and Okayama in the Siege of Ōsaka.