The earliest written reference to the game Go is generally recognized as the historical annal Zuo Zhuan referring to a historical event in 548 BC, with the name yì. Today, in China, it is known as weiqi. The game reached Japan in the 7th century CE, where it is called go or igo. The game became popular at the Japanese imperial court in the 8th century, and among the general public by the 13th century. The modern version of the game formalized in Japan in the 15th century. The then-best player in Japan, a Buddhist monk named Nikkai founded the Hon'inbō Go school, and several competing schools were founded soon after. These officially recognized and subsidized Go schools greatly developed the level of play and ranking players.
Despite its widespread popularity in East Asia, Go has been slow to spread to the rest of the world. Go did not start to become popular in the West until the end of the 19th century, when German scientist Oskar Korschelt wrote a treatise on the ancient Han Chinese game. By the early 20th century, Go had spread throughout the German and Austro-Hungarian empires, and in the US, Go came with Edward Lasker, who learned the game in Berlin. A Japanese Go Association, founded in 1924, supervises tournaments and rules and ranks players, both professional and amateur. The JGO organized the first World Go Amateur Championship in Tokyo, in 1979. Its success led to the founding of the International Go Federation in 1982.