Sun Tzu, originally named Sun Wu and also called Chang Qing, authored The Art of War in the sixth century BC. This military strategy book became the most influential book of war, and Sun Tzu became well-known for being a military strategist, but also an international relations realist. Stephen F. Kaufman, Hanshi, 10th Dan, is the holder of the highest rank attainable in the martial arts. His martial system, Hebi-ryu ( School of the Snake ), is recognized as one of the most effective combat methods in the world. His career spanning close to 60 years began in Okinawa in the 1950's. He's acknowledged as a founding father of American karate and has received countless awards and honors, including an induction to the World Karate Union Hall of Fame in 2011. Kaufman has authored many martial arts titles including Musashi's Book of Five Rings, The Way of the Modern Warrior and The Shogun's Scroll. Alexander Bennett is a professor of Japanese history, martial arts and Budo theory at Kansai University. He cofounded Kendo World, the first English-language journal dedicated to Kendo. He holds black belts in several martial disciplines-Kendo Kyoshi, 7th Dan; Iaido, 5th Dan; and Naginata, 5th Dan. His published works include Japan: The Ultimate Samurai Guide, Hagakure: The Secret Wisdom of the Samurai and Bushido Explained: The Japanese Samurai Code-A New Interpretation for Beginners.