Boniface IV

Hadrian's Pantheon had stood on the Campus Martius for nearly five centuries by the time Boniface IV became pope, a temple to all the gods with a coffered concrete dome that no builder of his own age could have raised. Rome by 609 was a diminished city under Byzantine administration, its population a fraction of the imperial figure, its temples closed by law since the end of the fourth century and increasingly stripped for building material. Boniface asked the emperor Phocas at Constantinople for the building, received it, and had it consecrated as the church of Saint Mary and the Martyrs, reportedly bringing cartloads of bones from the catacombs to lie beneath the new altar.

The consequence was structural as much as religious. Christian use kept the roof on. Almost every other temple of the city fell into ruin or was dismantled over the following centuries, while the Pantheon, protected by continuous liturgical use, survived with its dome and bronze doors, which is why it remains the best preserved building of ancient Rome. The reuse was not an isolated whim: it belongs to a wider late antique pattern in which the church absorbed the physical fabric of the old cult rather than erasing it, a pattern visible from Syracuse to Athens.

Later Western tradition draws a second line from the same day. Because the dedication honoured Mary together with all the martyrs, medieval and modern writers frequently treat it as an origin point for the feast of All Saints, which was kept in Rome in May before Gregory III and Gregory IV moved the observance to 1 November in the eighth and ninth centuries. The connection is a reasonable reading rather than a documented decree, and the older Eastern commemoration of all martyrs after Pentecost shows the idea did not begin with Boniface.

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.