Although (probably) not a Benedictine himself, he has some particular interest from a Benedictine perspective for his promotion of the cult of St Benedict in the 'Chronicon Melliti', a version of the Chronicle compiled by Isidore of Seville (d 636).
St Mellitus
St Mellitus was part of the group of clergy sent by St Gregory the Great to augment the mission to Anglo-Saxon England in 601.
He was initially appointed as bishop of London, but regime change there lead to his exile to Merovingian Gaul, and although he eventually returned to England, he did not return to London, but instead worked in the kingdom of Kent, where he eventually succeeded Archbishop Lawrence as Archbishop of Canterbury.
He is best known, though, as the recipient of a letter from St Gregory the Great on missionary strategy that was preserved in St Bede's Ecclesiastical History.
According to St Bede, St Mellitus was of noble birth. A papal register described him as an abbot of Frankia; various letters describe him as an abbot, but modern historians have suggested that this designation may have been just a courtesy title, conferred to make him the leader of the missionary group.
He was credited with one miracle in his life time, diverting a fire, and thus saving the Church building at Canterbury in 623. His cult was established early but was only ever local. Nonetheless, his feast is still celebrated on this date in a number of English dioceses.
The Chronicle
St Mellitus' particular interest from a Benedictine perspective though, lies in the edits and additions he made to Isidore of Seville's Chronicle, in particular, his addition of entries on St Gregory the Great and St Benedict to its lists of illustrious people.
The (on the face of it convincing) identification of bishop Mellitus as the author of the edits to Isidore's chronicle is fairly recent, coming in a paper by Luciano Cuppo (originally given at a 2010 conference, and since published in John S. Ott and Trpimir Vedriš, eds., Saintly Bishops and Bishops' Saints. (Series Colloquia 2.) Zagreb: Hagiotheca, 2012).
And that means that the comments made in it on St Benedict must date from between 615 (when the first edition of Isidore's Chronicle was completed) and St Mellitus' death in 624.
Accordingly, assuming the attribution is correct, the references to St Benedict in the Chronicle provide some of the earliest attestations to the importance of St Benedict outside of St Gregory's Dialogues, and are all the more important because they are clearly independent of St Gregory's work.
St Benedict as the illustrious father of monks
This particular edition of the Chronicle, according to Cuppo, provides two references to St Benedict.
The first gives the date of his death as 526, a much earlier than the traditional date of c542, and incompatible with the timing of several of incidents recorded in St Gregory's Life of the saint.
Cuppo is inclined to give Mellitus more weight than Gregory's account, but given recent work supporting the historicity of St Gregory's work, although attractive from some perspectives (it would settle the question of the priority of the Rule over that of the Master for one thing!) I'm inclined to disagree: for one thing, Gregory clearly cites his sources and clearly made deep inquiries about St Benedict's life and teaching.
The far more important and significant reference though is 'at that same time [565 - 578] Abbot Benedict, father of monks, was held in high esteem throughout Campania, Apulia, and the Roman province [ie Provence].'
Cuppo doesn't go into this, but St Gregory's Life mentions one other Italian foundation (Terracina) and also provides a possible link to Provence in the form of the friendship between St Benedict and Abbot Servandus, whose monastery had been founded by the then Governor of Provence, Liberius, who had in turn been saved by a miracle effected by St Caesarius of Arles (for more on this monastery Elizabeth Fentress et al, Walls and Memory. The Abbey of San Sabastiano at Alatri..., Brepols 2005).
Have we come full circle yet?
It has often been claimed, over the last several decades, that Benedictine monasticism was essentially a Carolingian invention.
Benedictine monasticism, so the revisionist storyline went, essentially died with St Benedict; St Gregory was not a Benedictine, but rather, assuming he wrote the Life at all (which they doubted), concerned with promoting homegrown saints and a particular type of spirituality rather than the Benedictine Rule as such.
But the evidence for something closer to the older, more traditional account (though perhaps a more nuanced one) of the spread of Benedictinism is steadily accumulating, and every little piece helps add to the picture.
