Sumo is often called Japan's national sport. Wrestlers, naked except for a special loincloth, face off, smash into each other, and battle for victory. Sumo is both a martial art and a highly stylized slice of traditional Japanese culture, with its own codes of appearance and conduct. Sumo originated centuries ago as a test of strength. It evolved over time into a harvest divination ritual. And in the 18th century, it developed into a popular form of mass entertainment. Sumo is more than just the "grand sumo" contested by professional wrestlers. Youth sumo toughens young minds and bodies, and there is women's sumo too. In recent years, a growing number of foreign wrestlers have internationalized sumo. Sumo is widely enjoyed in Japan, regardless of age or gender. On this edition of BEGIN Japanology, our theme is sumo. We examine the deep appeal of a sport that dates back over 1,500 years.