King Alfonso X of Spain (1221 - 1284), who is also known as "the Wise" due to his numerous scientific projects, commissioned a book on board and dice games towards the end of his life. He did not live to see the completion of this magnificent manuscript, which is adorned with many colorful illustrations. For Alfonso, games were more than just a pastime: they symbolized the nature of humanity and the world in which he lived. Therefore, his book of games represents one of the most significant sources for the cultural history of games. For the first time, this work describes chess, dice games, trick-track games, nine men's morris, and other games in a European language.