Why has the samurai sword always been such a powerful symbol of Japanese culture? Dr. Inazo Nitobe, the man pictured on Japan's 5,000-yen note, tried to answer that question for the world. As a Japanese diplomat at the League of Nations, he was asked by a western colleague how - without religious instruction - the Japanese could teach their children right from wrong. So in the year 1900, Dr. Nitobe wrote a book in English called Bushido - the code of the samurai. He wrote that this warrior code became the credo by which most Japanese lived their lives. And, he wrote, just as the code of the samurai is the soul of Japan, the sword is the soul of the samurai. For Dr. Nitobe, the sword is a work of art that represents the soul of the samurai. But originally the sword was not the samurai's weapon of choice. In the beginning, they fought from horseback, and their skill was with the bow and arrow. So why did the sword, not the bow and arrow, become so important to the samurai and to Japan? To find the answer we must go deep into the history and legends of this ancient land.