Gichin Funakoshi, founder of Shotokan karate, is generally credited with having introduced and popularized karate on the main islands of Japan. Actually many Okinawans were actively teaching, and are thus equally responsible for the development of karate. Funakoshi was a student of both Asato Ankō and Itosu Ankō (who had worked to introduce karate to the Okinawa Prefectural School System in 1902). During this time period, prominent teachers who also influenced the spread of karate in Japan included Kenwa Mabuni, Chojun Miyagi, Choki Motobu, Kanken Tōyama, and Kanbun Uechi. This was a turbulent period in history in the region. It includes Japan's annexation of the Okinawan island group in 1874, the First Sino-Japanese War (1894–1895), the Russo-Japanese War (1904–1905), the annexation of Korea, and the rise of Japanese expansionism (1905–1945).

Japan was invading China at the time, and Funakoshi knew that the art of Tang/China hand would not be accepted; thus the change of the art's name to "way of the empty hand." The dō suffix implies that karatedō is a path to self knowledge, not just a study of the technical aspects of fighting. Like most martial arts practiced in Japan, karate made its transition from -jutsu to -dō around the beginning of the 20th century. The "dō" in "karate-dō" sets it apart from karate "jutsu", as aikido is distinguished from aikijutsu, judo from jujutsu, iaido from iaijutsu and Taido from Taijutsu.