Jacobus de Voragine was an Italian chronicler and archbishop of Genoa. He was the author, or more accurately the compiler, of the Golden Legend, a collection of the legendary lives of the greater saints of the medieval church that was one of the most popular religious works of the Middle Ages.

Jacopo Aconcio was an Italian jurist, theologian, philosopher and engineer. He is now known for his contribution to the history of religious toleration.

Jacopo Ferretti was an Italian writer, poet and opera librettist. His name is sometimes written as Giacomo Ferretti.

Jacopo Nardi (1476 – c. 1563) was an Italian historian from Florence.

Jacopo Sannazaro was an Italian poet, humanist, member and head of the Accademia Pontaniana from Naples.

Giacomo Zabarella was an Italian Aristotelian philosopher and logician.

Jacopone da Todi, O.F.M. was an Italian Franciscan friar from Umbria. He wrote several laude in the local vernacular. He was an early pioneer in Italian theatre, being one of the earliest scholars who dramatised Gospel subjects.

Jacqueline Baird is popular English writer of over 30 romance novels since 1988.

Jacqueline Briggs Martin is an American author of children's literature and a teacher of creative writing. Her books have received several awards including, Caldecott Medal (1999), Golden Kite Award, Lupine Award, Award for Excellence in Children's Literature from the Sterling North Society, and the Green Earth Award (2018). She has taught at Cornell College, University of Iowa, The Loft Literary Center, and is on faculty at Hamline University.

Jacqueline Briskin, née Orgell was a British-born American writer specializing in historical fiction from 1970 to 1995. Her books regularly appear on the New York Times bestseller's list. She was a main Selection of the Literary Guild and Doubleday Book Club seven times, her novels were translated into 26 languages, and has sold 23,000,000 copies worldwide.