Ruy López de Segura

Rodrigo (Ruy) López de Segura (c. 1530 – c. 1580) was a Spanish priest and later bishop in Segura and is also widely considered as the Father of Chess Theory.

His 1561 book, Libro de la invención liberal y arte del juego del Axedrez, is said to be the beginning of a long road to document chess strategy. It was one of the first definitive books about modern chess in Europe, only after Pedro Damiano's 1512 book. He gave a detailed description of the Spanish Opening in the book, and the Opening is now commonly known as the Ruy López.

Ruy López was born in Zafra near Badajoz, probably of Converso Jewish descent, and he studied and lived in Salamanca. He was considered the strongest player in the world in the 1560’s, achieving this status with stunning victories in Rome over Italy's finest players; Giovanni Leonardo Di Bona da Cutri, a Calabrian lawyer, and Paolo Boi. 

The following is a short game between Ruy López and Giovanni Leonardo Di Bona da Cutri, played in Rome in 1560.

In 1574–75 the Italians got revenge in the first known international Chess Tournament, which was held, at the invitation of King Philip II of Spain, at the Royal Court of Spain in El Escorial, close to Madrid. Also in the tournament was López’s countryman, Alfonso Ceron, who came in last.