Archdeacon (Gr. chief minister), an ecclesiastical dignitary, the assistant of the bishop. At the beginning of the 4th century there was in almost every diocese an archdeacon, invested with authority by the bishop, particularly in the administration of temporal affairs. To him belonged the care of preserving public order and propriety during the divine service, of guarding the ornaments of the church, and of tending the poor throughout the diocese. He was called the hand and the eye of the bishop, and, from his influential position, became recognized as superior to the priesthood, though retaining only the deacon's consecration. As overseer of the deacons and of the younger clergy who were not yet consecrated, he had the supervision of their education and studies, so that a certificate from him was required before their ordination to the priesthood. When the dioceses began to enlarge, and the metropolitan churches to attach to themselves the neighboring country congregations, it became necessary to divide the diocese into a number of archdeaconries. The archdeacons increased in independence and power till the 13th century, when they claimed a jurisdiction proper to themselves, and the right to appoint their own subordinates.

Several synods sought directly to limit their prerogatives, and it was finally decreed by the council of Trent that henceforth the archdeacons should hold their right of supervision only by the bishops' permission. From that time they have gradually disappeared from many dioceses. England is divided into 67 archdeaconries, and it is imperative upon each archdeacon to visit his district at least once in three years. It belongs to him to see that the churches and chancels are in repair, that everything is done conformably to the canons, and to hear from the churchwardens any representations of public scandal. The archdeacons are appointed by their respective bishops.