Saint Dominic, Spanish priest, founded the Dominican Order (born 1170)

Saint Dominic,, also known as Dominic de Guzmán, was a Castilian Catholic priest and the founder of the Dominican Order. He is the patron saint of astronomers and natural scientists, and he and his order are traditionally credited with spreading and popularizing the rosary.

The Order of Preachers, commonly known as the Dominican Order, is a Catholic mendicant order of pontifical right that was founded in France by the Castilian priest Dominic de Guzmán. It was approved by Pope Honorius III via the papal bull Religiosam vitam on 22 December 1216. Members of the order, who are referred to as Dominicans, generally display the letters OP after their names, standing for Ordinis Praedicatorum, meaning 'of the Order of Preachers'. Membership in the order includes friars, nuns, active sisters, and lay or secular Dominicans. More recently, there have been a growing number of associates of the religious sisters who are unrelated to the tertiaries.