Jordan of Pisa was a 13th-century Dominican theologian and a pioneering preacher known for delivering sermons in the vernacular Italian. Born in Pisa, he studied in Paris and Bologna before dedicating his life to the Dominican Order. He gained widespread fame for his extensive memory of theological texts and his ability to engage large crowds through his musical, accessible preaching style. His work in Florence significantly influenced local morality and public life through the promotion of Thomistic doctrine.