Theophylact was an archdeacon of the Roman Church. After the death of Pope Stephen II in 757, a faction wanted to place him on the Holy See, but the majority chose the deceased Pope's brother Paul as successor.<ref>Template:Cite book</ref><ref>Template:Cite book</ref> Theophylact remained in the papal service, in 794 serving as one of Adrian I's legates to the Synod of Frankfurt.