Lifespan: Eiroku 6 (1563) to 7/20 of Genna 6 (1620)
Rank: bushō, daimyō
Title: Junior Fifth Rank (Lower), Governor of Iga
Domain: Yamato-Gose (first head)
Lord: Toyotomi Hidenaga → Toyotomi Hideyasu → Toyotomi Hideyoshi → Toyotomi Hideyori → Tokugawa Ieyasu → Tokugawa Hidetada
Father: Kuwayama Shigeharu
Siblings: Kazushige, Motoharu, Sadaharu
Children: Kiyoharu, Sadaharu, Eiharu, daughter (formal wife of Okabe Nobukatsu)
Kuwayama Motoharu served as a bushō and daimyō during the Azuchi-Momoyama and early Edo periods.
Motoharu also used the name of Naoharu. He was the first head of the Yamato-Gose domain and held the titles of Junior Fifth Rank (Lower) and the Governor of Iga.
In 1563, Motoharu was born as the second son of Kuwayama Shigeharu in Owari Province. Motoharu served Toyotomoi Hidenaga and Toyotomi Hideyasu. He deployed, along with his nephew, Kuwayama Kazuharu, to the Korean Peninsula during the Bunroku Campaign.
In 1594, after the fall of Hideyasu and end of the Yamato-Toyotomi family, he served directly under Toyotomi Hideyoshi and, in 1596, was allocated a fief of 10,000 koku in Yamato-Gose by his father, Shigeharu.
In 1600, at the Battle of Sekigahara, Motoharu joined the Eastern Army, and contributed by killing the head of the infantry division under the command of Ōtani Yoshitsugu. After the war, his fief was increased by 2,000 koku in the Katsujō District. Motoharu served as the first head of the Gose domain (12,000 koku, later assigning 2,000 koku to his father).
Later, in 1606, upon the death of his father, he inherited a fief of 6,000 koku and, in 1609, after the removal of his older brother, Kuwayama Kiyohara, from his position, was granted a fief of 10,000 koku in the Izumi-Tanagawa domain, becoming a daimyō with a fief of 26,380 koku.
In 1614, at the Siege of Ōsaka, Motoharu deployed at Tennōjiguchi under the command of Tōdō Takatora. At the Summer Campaign of the Siege of Ōsaka, Motoharu joined his younger brother, Kuwayama Sadaharu, and nephew, Kuwayama Kazunao, to fight in the vanguard division led by Mizuno Katsunari at the Battle of Dōmyōji. He took seventeen heads. After the war, he joined his brother, Kōriki Tadafusa, to pursue remnants of the defeated army.
Motoharu learned the tea ceremony from Furuta Shigenari.
Motoharu died on 7/20 of Genna 6 (1620) at the age of fifty-eight. He was succeeded by his second son, Sadaharu.