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The village is the birthplace of Haguroyama Masaji (羽黒山 政司, November 18, 1914 - October 14, 1969) who was sumo's 36th yokozuna. Haguroyama earned the rank in May 1941 and held the title for twelve years and three months. It remains an all-time record today.
During his career Haguroyama won seven top division championships and was runner-up on six other occasions.
In Nakanokuchi, there is a museum dedicated to Haguroyama and a bronze statue of the famous wrestler wearing his shimenawa (the knotted rope indicating his rank as yokozuna).
References
住民基本台帳人口移動報告年報 (in Japanese). 総務庁統計局. 2005. p. 139. 3月21日に白根市,豊栄市,小須戸町,横越町,亀田町,岩室村,西川町,味方村,潟東村,月潟村,中之口村及び新津市は新潟市に編入された。