Yabu was born in Shuri, Okinawa, on September 23, 1866. He was the oldest son of Yabu Kenten and Shun Morinaga. He had three brothers, three sisters, and three half-sisters. On March 19, 1886, he married Takahara Oto. As a young man, Yabu received training in Shōrin-ryū karate. His teachers included both Matsumura Sōkon and Itosu Anko. Yabu joined the Japanese Army in 1891. He served in Manchuria during the First Sino-Japanese War of 1894-1895. He received promotion to lieutenant, but to subsequent students, he was often known as gunso, or sergeant. Following separation from the service, Yabu studied at Shuri's Prefectural Teacher's Training College, and in 1902, he became a teacher at Shuri's Prefectural School Number One. In 1908, Yabu's oldest son, Kenden, went to Hawaii. In 1912, Kenden went to California. In the USA, Kenden Yabu became known as Kenden Yabe, after a method of transliteration then being used on Japanese passports. In 1919, Kenden Yabe married, and in 1921, his wife became pregnant. Yabu Kentsu immediately went to California to visit his son. However, Kenden Yabe and his wife only had daughters. Thus, Yabu Kentsu went back to Okinawa disappointed. Yabu visited the United States twice, once during 1921-1922, and again in 1927. During the second visit, he returned to Okinawa via Hawaii. He spent about nine months in the Territory. He spent most of his time on Oahu, but he also visited other islands. In Honolulu, he gave two public demonstrations of karate at the Nuuanu YMCA. In 1936, Yabu visited Tokyo. While there, he visited the young Shōshin Nagamine, who later became another well-known karate teacher. Yabu died at Shuri, Okinawa, on August 27, 1937.
Influence on Karate
As a former soldier, Yabu has been credited with helping make Okinawan karate training more militaristic. That is, students were expected to line up in rows, and respond by the numbers. If so, this was probably part of the general militarization of Japanese athletics common during the early 20th century. However, there is no doubt that his methods involved much rote repetition. His favorite kata reportedly included Gojūshiho and naihanchi.
