Boniface IV had been a deacon under Gregory the Great, whose mission to the Anglo-Saxons was barely a decade old when Boniface took the papal office, and his pontificate shows the mission still tied closely to Rome. In 610 he convened a synod in the city on the ordering of monastic life. Among those present was Mellitus, whom Gregory's mission had made the first bishop of the East Saxons at London, and who had come to Rome to seek guidance for a church still being built from nothing in a kingdom that had been pagan within living memory. Bede records that Mellitus carried the synod's decrees back with him, along with letters from the pope for Archbishop Laurence and the English clergy.
That transmission is the reason a small Roman gathering matters at all outside Italy. The Anglo-Saxon church in 610 had no settled canon law of its own, no monastic rule universally in force, and no resolution yet of the sharp differences it would later fight out with the Irish tradition over the dating of Easter and the form of the tonsure at the Synod of Whitby. Decrees carried by hand from a Roman synod were a working answer to a practical shortage.
Boniface himself lived out the same monastic preference he legislated for, giving over his family house in Rome as a monastery, a step his biographer in the Liber Pontificalis records approvingly. His pontificate coincided with famine, plague and epidemic disease in the city, and after his death he was venerated as a saint, his relics eventually moved into Saint Peter's.