Pope Gregory I (Latin: Gregorius I) (c. 540 – 12 March 604), better known in English as Gregory the Great, was pope from 3 September 590 until his death. Gregory is well known for his writings, which were more prolific than those of any of his predecessors as pope.

Throughout the Middle Ages he was known as “the Father of Christian Worship” because of his exceptional efforts in revising the Roman worship of his day.

He is also known as St. Gregory the Dialogist in Eastern Orthodoxy because of his Dialogues. For this reason, English translations of Orthodox texts will sometimes list him as "Gregory Dialogus". He was the first of the popes to come from a monastic background. Gregory is a Doctor of the Church and one of the Latin Fathers. He is considered a saint in the Roman Catholic Church, Eastern Orthodox Church, Anglican Communion, and some Lutheran churches. Immediately after his death, Gregory was canonized by popular acclaim. The Protestant reformer, John Calvin, admired Gregory and declared in his Institutes that Gregory was the last good pope. He is the patron saint of musicians, singers, students, and teachers.