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The first known chess tournament took place in Madrid in 1575, under the patronage of King Philip II. Four of the best chess players of the time competed in this tournament: the Spanish priests Ruy López de Segura and Alfonso Cerón, and the Italians Paolo Boi and Leonardo da Cutri.
Ruy Lopez de Segura, recognized as one of the best chess players in the world at that time, had already defeated Paolo Boi and Leonardo da Cutri in several previous games. However, in the tournament, the Italians managed to win three consecutive games after losing the first two, thus securing victory in what is considered the first chess tournament in the world.
As for additional details about the tournament, we know that it was held at El Escorial and was a grand occasion, with many prominent members of the court present. Ruy Lopez de Segura had been sent to Italy in 1573 by King Philip to carry out a diplomatic mission and, during his time there, he reasserted himself as the best chess player in the world. For his victories, the king rewarded him on several occasions, in one of them, he gave him a pendant-chain with a golden tower.