A physicist. Born to a samurai family of the Omura clan. Graduated from the Imperial University in 1887. In 1893 he studied in Germany and after his return to Japan, he became a professor at the Imperial University of Tokyo. He also was involved in the establishment of the Riken research institute. In 1903 he published a paper on the atomic model and received international recognition, and pioneered physics studies in Japan. In 1937 he was awarded the 1st Order of Culture. The first president of Osaka Imperial University and president of the Imperial Academy. He served as a member of the House of Peers from 1934 to 1950.