Sokon Matsumura was a renowned warrior of his time; he has been called the "Miyamoto Musashi" of Okinawa. However, while he is often referred to as the "founder" of Shorin-ryu, he did not invent all the components the style, and perhaps didn't refer to it as "Shorin-ryu" himself. It is quite possible that he synthesized his knowledge of Okinawan arts with Chinese fighting styles that he learned on his travels and taught it as a coherent system to some eager students, who subsequently refined it, labelled it, and passed it on. (Highlighting Shorin-Ryu's Chinese heritage is the fact that "Shorin" is the Japanese pronunciation of the Chinese 少林, "Shaolin"; "ryu" means "school", or "style" or "stream".)
Along with being a style on its own, Shorin-ryu is also perhaps the most influential single ancestor of modern Japanese karate. One of Matsumura's best-known students, Anko Itosu became a great practitioner and teacher of Okinawan karate and developed the five Pinan kata, which are now taught not only in Shorin-ryu, but also in a wide variety of Okinawan, Japanese and derived martial arts.
It is also believed by some that the first two Pinan kata's were actually developed by Matsumura and the last three by Itosu. In addition, Itosu and another student of Matsumura's named Anko Azato were among the primary influences on a fellow Okinawan named Gichin Funakoshi.
Funakoshi introduced his Okinawan martial arts to mainland Japan in 1922, and in subsequent decades was instrumental in developing what he termed simply "karate" or "karate-do" as a popular Japanese sport and art. (The style Funakoshi taught on mainland Japan is now called Shotokan karate.)