Ruy López de Segura

Rodrigo (Ruy) López de Segura (c. 1530 – c. 1580) was a Spanish priest and later bishop in Segura whose 1561 book Libro de la invención liberal y arte del juego del Axedrez was one of the first definitive books about modern chess in Europe, preceded only by Pedro Damiano's 1512 book.
He was born in Zafra near Badajoz, and he studied and lived in Salamanca. In 1560 he won a match against Leonardo di Bona in Rome. In 1574–75 he lost 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, to Leonardo di Bona, a Calabrian lawyer, and to Paolo Boi, but placing ahead of 4th (and last) place finisher Alfonso Ceron.

The Ruy Lopez Opening (1.e4 e5 2.Nf3 Nc6 3.Bb5) is named after him, as is a variation in the Petroff Defence (1.e4 e5 2.Nf3 Nf6 3.Nxe5 Qe7).