Justus was a 7th-century missionary and religious leader who served as the fourth Archbishop of Canterbury. Sent from Rome by Pope Gregory the Great to convert the Anglo-Saxons, he arrived in England as part of a secondary group of missionaries. Before his elevation to the archiepiscopate, he served as the first bishop of Rochester. During his career, he navigated significant political shifts, including a period of exile in Gaul following the death of King Æthelberht, before returning to his duties in Kent.