Pope Boniface III

[2] While serving as a deacon, Boniface impressed Pope Gregory I, who described him as a man "of tried faith and character" and selected him to be papal apocrisiarius to the imperial court in Constantinople in 603.

This proved important when he was instructed by Pope Gregory to intercede with Emperor Phocas on behalf of Bishop Alcison of Cassiope on the island of Corcyra.

Alcison found his episcopate being usurped by Bishop John of Euria in Epirus, who had fled his home along with his clergy to escape from attacks by the Slavs and Avars.

[2] Boniface was elected to succeed Pope Sabinian, who died in February 606, but his return from Constantinople to Rome was delayed by almost a year.

Some authorities believe that it was to allow Boniface to complete his work in Constantinople, but the more widely held belief is that imperial ratification was delayed due to dissension between those who supported the policies of Gregory I and those who did not.