Aachen , in French, Aix-la-Chapelle, the name by which the city is generally known in Latin Aquæ Grani, later Aquisgranum, is the capital of a presid

 Aaron

 Abaddon

 Abandonment

 Pedro Abarca

 Abarim

 Abba

 Antoine d'Abbadie

 Abban

 Abbé

 Jean Baptiste Abbeloos

 Abbess

 Abbey

 Abbo Cernuus

 St. Abbon

 Abbot

 Henry Abbot

 Methods of Abbreviation

 Ecclesiastical Abbreviations

 Abbreviators

 Abdera

 Abdias

 Abdias of Babylon

 Abdication

 Sts. Abdon and Sennen

 Abduction

 Abecedaria

 Abecedarians

 Abel (1)

 Abel (2)

 Peter Abelard

 Louis Abelly

 Abenakis

 Abraham-ben-Méir Aben-Ezra

 Inscription of Abercius

 John Abercromby

 Robert Abercromby

 Diocese of Aberdeen

 University of Aberdeen

 Moritz von Aberle

 Legend of Abgar

 Abiathar

 Abila

 Abbey of Abingdon

 Thomas Abington

 Missions among the Abipones

 Abisai

 Abjuration

 Abo

 Abner

 Abomination of Desolation

 Abortion

 Physical Effects of Abortion

 Charles François d'Abra de Raconis

 Don Isaac Abrabanel

 Abraham

 Abraham (in Liturgy)

 Bosom of Abraham

 Abraham a Sancta Clara

 Abraham Ecchelensis

 Abrahamites

 Nicholas Abram

 Abrasax

 Absalom

 Absalon of Lund

 Absinthe

 Absolute

 Absolution

 Abstemii

 Abstinence

 Physical Effects of Abstinence

 Abstraction

 Abthain

 Theodore Abucara

 Abundius

 Abydus

 Abyss

 Abyssinia

 Acacia

 Acacians

 Acacius, Bishop of Beroea

 Acacius, Bishop of Caesarea

 Acacius, Patriarch of Constantinople

 St. Acacius

 Roman Academies

 French Academy

 Acadia

 Acanthus (see)

 Acanthus (plant)

 Acathistus

 St. Acca

 Accaron

 Accentus Ecclesiasticus

 Acceptance

 Acceptants

 Accession

 Diocese of Arras

 Councils of Arras

 Pablo José Arriaga

 Juan Arricivita

 Nicola Arrighetti

 Nicolò Arrighetti

 Arsacidæ

 Arsenius Autorianos

 St. Arsenius

 Arsinoe

 Accessus

 Artemon

 James Arthur

 Thomas Arthur

 Articles of Faith

 Organic Articles

 Artoklasia

 Bachelor of Arts

 Faculty of Arts

 Master of Arts

 Seven Liberal Arts

 Acciajuoli

 Artvin

 Thomas Arundel

 Thomas Arundell

 St. Asaph

 Ascalon

 Ascelin

 Ascendente Domino

 Ascension

 Feast of the Ascension

 Asceticism

 Accident

 Joseph, Ritter von Aschbach

 Diocese of Ascoli-Piceno

 Diocese of Ascoli, Satriano, and Cirignola

 Aseity

 Aseneth

 Aser

 Asgaard

 Ash Wednesday

 George Ashby

 Thomas Ashby

 Acclamation

 Ashes

 Ven. Ralph Ashley

 John Ashton

 Ven. Roger Ashton

 Asia

 Asia Minor

 Asiongaber

 Robert Aske

 Asmodeus

 Aspendus

 Acclamation (in Papal Elections)

 Asperges

 Martin Aspilcueta

 The Ass (in Caricature of Christian Beliefs and Practices)

 Prefecture Apostolic of Assam

 Assemani

 Assemblies of the French Clergy

 John Asser

 Feast of Asses

 Assessor of the Holy Office

 Assessors

 Biblical Accommodation

 St. Assicus

 Assideans

 Physiological Assimilation

 Psychological Assimilation

 Diocese of Assisi

 Assistant at the Pontifical Throne

 Assize of Clarendon

 Volume 1

 Volume 3

 Assizes of Jerusalem

 Accomplice

 Ignaz Assmayer

 Right of Voluntary Association

 Association of Ideas

 Association of Priestly Perseverance

 Pious Associations

 Assuerus

 Little Sisters of the Assumption

 Sisters of the Assumption

 Feast of the Assumption of the Blessed Virgin Mary

 Assur (1)

 Francesco Accursius

 Assur (2)

 Assyria

 Asterisk

 Asterius

 Diocese of Asti

 Aston

 Diocese of Astorga

 Astrology

 Astronomy

 Astronomy in the Bible

 Paul-Thérèse-David d'Astros

 Acephali

 Jean Astruc

 Atahuallpa

 Juan Santos Atahualpa

 Atavism

 Vicariate Apostolic of Athabasca

 Athanasian Creed

 St. Athanasius

 Atheism

 Abbey of Athelney

 Athenagoras

 Archdiocese of Acerenza

 Athenry

 Christian Athens

 Modern Diocese of Athens

 Joseph Athias

 Mount Athos

 Juan de Atienza

 James Atkinson

 Nicholas Atkinson

 Paul Atkinson of St. Francis

 Sarah Atkinson

 Achab

 Ven. Thomas Atkinson

 Atom

 Atomism

 Day of Atonement

 Doctrine of the Atonement

 Atrib

 Atrium

 Attainder

 St. Attala

 Attalia

 Achaia

 Michael Attaliates

 Atticus

 Councils of Attigny

 Attila

 Jean Denis Attiret

 Atto

 Atto of Pistoia

 Atto of Vercelli

 St. Attracta

 Divine Attributes

 Achaicus

 Attrition

 Attuda

 Jean-Michel-d'Astorg Aubarède

 Jean-Antoine d'Aubermont

 Joseph Aubery

 François Hédelin, Abbé d'Aubignac

 Pierre d'Aubusson

 Archdiocese of Auch

 Diocese of Auckland

 Auctorem Fidei

 Achaz

 Pontifical Audiences

 Giovanni Battista Audiffredi

 J. M. Vincent Audin

 Guglielmo Audisio

 Auditor

 Audran

 Leopold Auenbrugger

 Jobst Bernhard von Aufsees

 Edmond Auger

 Augilæ

 Lucas d'Achéry

 Diocese of Augsburg

 Synods of Augsburg

 Augusta

 Augustin von Alfeld

 Rule of Saint Augustine

 St. Augustine of Canterbury

 St. Augustine of Hippo

 Teaching of St. Augustine of Hippo

 Works of St. Augustine of Hippo

 Augustinians of the Assumption

 Antonius Augustinus

 Augustinus-Verein

 Achiacharus

 Augustopolis

 Augustus

 Aumbry

 St. Aunarius

 Aurea

 Aurelian

 Aureliopolis

 Aurelius

 Marcus Aurelius Antoninus

 Petrus Aureoli

 Achimaas

 Auriesville

 Giovanni Aurispa

 Aurora Lucis Rutilat

 Ausculta Fili

 Decimus Magnus Ausonius

 John Austin

 Australia

 St. Austrebertha

 St. Austremonius

 Austro-Hungarian Monarchy

 Achimelech

 Authentic

 Authenticity of the Bible

 Civil Authority

 Authorized Version

 Autocephali

 Autos Sacramentales

 Ambrose Autpert

 Joseph Autran

 Diocese of Autun

 Auxentius

 Achitopel

 Councils of Auxerre

 Auxiliary Bishop

 Auxilius of Naples

 Ava

 Nicola Avancini

 Avarice

 Avatār

 Pierre du Bois, Baron d'Avaugour

 Ave Maris Stella

 Ave Regina

 Diocese of Achonry

 Diocese of Avellino

 Avempace

 Fernando Avendano

 Averroes

 Diocese of Aversa

 Avesta

 Theological Aspects of Avesta

 Avicebron

 Avicenna

 Avignon

 Achor Valley

 University of Avignon

 Diocese of Avila

 Francisco de Avila

 Sancho de Avila

 St. Avitus

 Order of Aviz

 Council of Avranches

 Philippe Avril

 Axum

 Diocese of Ayacucho

 Achrida

 Fray Francisco de Ayeta

 Lucas Vásquez de Ayllón

 James Ambrose Dominic Aylward

 Aymará

 Aymeric of Piacenza

 Féliz de Azara

 Aristaces Azaria

 Brother Azarias

 Luiz de Azevedo

 Juan Azor

 Johann Heinrich Achterfeldt

 Azores

 Azotus

 Aztecs

 Azymes

 Azymites

 Theodore William Achtermann

 Valens Acidalius

 Diocese of Aci-Reale

 Leopold Ackermann

 Acmonia

 Acoemetae

 Acolouthia

 Acolyte

 Joaquín Acosta

 José de Acosta

 Diocese of Acquapendente

 Acquaviva

 Claudius Acquaviva

 Diocese of Acqui

 Acre

 Acrostic

 Acta Pilati

 Acta Sanctæ Sedis

 Acta Sanctorum Hiberniæ

 Acta Triadis Thaumaturgæ

 Act of Settlement (Irish)

 Charles Januarius Acton

 John Acton

 John Emerich Edward Dalberg Acton, Baron Acton

 John Francis Edward Acton

 Canonical Acts

 Human Acts

 Indifferent Acts

 Acts of the Apostles

 Acts of Roman Congregations

 Actus et Potentia

 Actus primus

 Actus Purus

 Acuas

 St. Adalard

 Adalbert

 Adalbert I

 St. Adalbert (of Bohemia)

 St. Adalbert (of Germany)

 Ad Apostolicae Dignitatis Apicem

 Ad Limina Apostolorum

 Ad Sanctam Beati Petri Sedem

 Ad Universalis Ecclesiae

 Adam

 Adam in Early Christian Liturgy and Literature

 Books of Adam

 Adam of Bremen

 Adam of Fulda

 Adam of Murimuth

 Adam of Perseigne

 Adam of St. Victor

 Adam of Usk

 John Adam

 Nicholas Adam

 Adam Scotus

 Andrea Adami da Bolsena

 Adamites

 St. Adamnan

 James Adams

 Ven. John Adams

 Diocese of Adana

 Adar

 Ferdinando d'Adda

 Addas

 Liturgy of Addeus and Maris

 Ecclesiastical Addresses

 Archdiocese of Adelaide

 St. Adelaide, Abbess

 St. Adelaide (Adelheid)

 John Placid Adelham

 Adelmann

 Adelophagi

 Vicariate Apostolic of Aden

 Adeodatus

 Pope St. Adeodatus

 Adeste Fideles

 Adjuration

 Administrator

 Administrator (of Ecclesiastical Property)

 Canonical Admonitions

 Admont

 St. Ado of Vienne

 Adonai

 Adonias

 Adoption

 Canonical Adoption

 Supernatural Adoption

 Adoptionism

 Adoration

 Perpetual Adoration

 Francis Adorno

 Adoro Te Devote

 Diocese of Adria

 Pope Adrian I

 Pope Adrian II

 Pope St. Adrian III

 Pope Adrian IV

 Pope Adrian V

 Pope Adrian VI

 St. Adrian of Canterbury

 Adrian of Castello

 Adrianople

 Christian Kruik van Adrichem

 Adso

 Diego Francisco Aduarte

 Adullam

 Adulteration of Food

 Adultery

 Advent

 Adventists

 Book of Advertisements

 Advocates of Roman Congregations

 Advocates of St. Peter

 Advocatus Diaboli

 Advocatus Ecclesiæ

 Advowson

 Adytum

 St. Aedan of Ferns

 Aedh of Kildare

 Bl. Aegidius of Assisi

 Ægidius of Viterbo

 Aelfric, Abbot of Eynsham

 Ælnoth

 St. Ælred

 Æneas of Gaza

 St. Aengus (the Culdee)

 Ænon

 Æons

 Aër

 Aërius of Pontus

 Æsthetics

 Æterni Patris (Pius IX)

 Æterni Patris (Leo XIII)

 Aëtius

 Affinity (in the Bible)

 Affinity (in Canon Law)

 Affirmation

 Afflighem

 Denis Auguste Affre

 St. Afra

 Africa

 Early African Church

 African Liturgy

 African Synods

 Agabus

 Agape

 Agapetae

 Agapetus

 Pope St. Agapetus I

 Pope Agapetus II

 William Seth Agar

 St. Agatha

 Agathangelus

 Agathias

 Pope St. Agatho

 Agaunum

 Agostini Agazzari

 Council of Agde

 Canonical Age

 Age of Reason

 Diocese of Agen

 Agents of Roman Congregations

 Aggeus (Haggai)

 Unjust Aggressor

 Raymond d'Agiles

 St. Agilulfus

 Agios O Theos

 Giuseppe Agnelli

 Fra Guglielmo Agnelli

 Bl. Agnellus of Pisa

 Andreas Agnellus of Ravenna

 St. Agnes of Assisi

 Bl. Agnes of Bohemia

 St. Agnes of Montepulciano

 St. Agnes of Rome

 Maria Gaetana Agnesi

 Agnetz

 Agnoetae

 Agnosticism

 Agnus Dei

 Agnus Dei (in Liturgy)

 Agonistici

 Agony of Christ

 Paolo Agostini

 Bl. Agostino Novello

 Charles Constance César Joseph Matthieu d'Agoult

 Archdiocese of Agra

 Agram

 Agrapha

 Agrarianism

 Maria de Agreda

 Agria

 St. Agricius

 Alexander Agricola

 George Agricola

 Rudolph Agricola

 Heinrich Cornelius Agrippa of Nettesheim

 Agrippinus

 Diocese of Aguas Calientes

 Joseph Saenz de Aguirre

 Ahicam

 Ahriman and Ormuzd

 Johann Caspar Aiblinger

 Gregor Aichinger

 St. Aidan of Lindisfarne

 Duchess of Aiguillon

 Mary Aikenhead

 St. Ailbe

 St. Aileran

 Family of d'Ailleboust

 Pierre d'Ailly

 Mateo Aimerich

 Diocese of Aire

 Giacomo Maria Airoli

 Aisle

 Aistulph

 Archdiocese of Aix

 Councils of Aix-en-Provence

 Diocese of Ajaccio

 Akhmin

 Michael and Nicetas Akominatos

 Alabama

 Alabanda

 Alabaster

 Diocese of Alagoas

 Pietro Alagona

 Alain de l'Isle

 Alalis

 Lucas Alaman

 Niccolò Alamanni

 Alan of Tewkesbury

 Alan of Walsingham

 Alanus de Rupe

 Alaska

 Diocese of Alatri

 Alb

 Diocese of Alba Pompeia

 St. Alban

 Albanenses

 Albania

 Albani

 Albano

 Diocese of Albany

 Diocese of Albenga

 Niccolo Albergati

 Alberic of Monte Cassino

 Alberic of Ostia

 Albero de Montreuil

 Giulio Alberoni

 Albert

 Albert II

 Bl. Albert

 St. Albert

 Bl. Albert Berdini of Sarteano

 Albert of Aachen

 Albert of Brandenburg

 Albert of Castile

 Albert of Stade

 Leandro Alberti

 Leone Battista Alberti

 Nicolò Albertini

 John Baptist Albertrandi

 Bl. Albertus Magnus

 Archdiocese of Albi

 Council of Albi

 Juan de Albi

 Sigismund Albicus

 Albigenses

 Albinus

 Johann G. Albrechtsberger

 Albright Brethren

 Afonzo de Albuquerque

 University of Alcalá

 Military Order of Alcántara

 Antonio de Alcedo

 Alchemy

 St. Alcmund

 Andrea Alciati

 Alcimus

 John Alcock

 Alcoholism

 Alcuin

 St. Aldegundis

 Aldersbach

 Aldfrith

 St. Aldhelm

 St. Aldric

 Ulissi Aldrovandi

 Leonard Alea

 Phillipe Alegambe

 Francisco Xavier Alegre

 Joseph Sadoc Alemany

 Giulio Alenio

 Archdiocese of Aleppo

 Diocese of Ales and Terralba

 Diocese of Alessandria della Paglia

 Galeazzo Alessi

 Diocese of Alessio

 Alexander

 Alexander (Early Bishops)

 Pope St. Alexander I

 Pope Alexander II

 Pope Alexander III

 Pope Alexander IV

 Pope Alexander V

 Pope Alexander VI

 Pope Alexander VII

 Pope Alexander VIII

 St. Alexander

 St. Alexander (II)

 St. Alexander (of Alexandria)

 Bl. Alexander Briant

 Alexander Natalis

 Alexander of Abonoteichos

 Alexander of Hales

 Alexander of Lycopolis

 Bl. Alexander Sauli

 Dom Jacques Alexandre

 Alexandria

 Councils of Alexandria

 Church of Alexandria

 Diocese of Alexandria

 Alexandrian Library

 Alexandrine Liturgy

 Alexian Nuns

 Alexians

 St. Alexis Falconieri

 St. Alexius

 Count Vittorio Alfieri

 Pietro Alfieri

 Alfonso de Zamora

 Alfonso of Burgos

 Michael Alford

 Alfred the Great

 St. Alfrida

 St. Alfwold

 Alger of Liége

 Diocese of Alghero

 Archdiocese of Algiers

 Algonquins

 Diocese of Alife

 Alimentation

 Alimony

 Aliturgical Days

 All Hallows College

 All Saints

 All Souls' Day

 Allah

 Diocese of Allahabad

 Paul Allard

 Leo Allatius

 Joseph Allegranza

 Antonio Allegri

 Gregorio Allegri

 Alleluia

 Jean Allemand

 Edward Patrick Allen

 Frances Allen

 George Allen

 John Allen (I)

 John Allen (II)

 William Allen

 August Allerstein

 Thomas William Allies

 Joseph Franz Allioli

 William Allison

 Allocution

 Allori

 William Allot

 Claude Allouez

 Alma

 Alma Redemptoris Mater

 Diego de Almagro

 John Almeida

 Diocese of Almeria

 Camillo Almici

 Ven. John Almond

 John Almond

 Oliver Almond

 Alms and Almsgiving

 St. Alnoth

 Alogi

 St. Aloysius Gonzaga

 A and Ω

 Alpha and Omega (in Jewish Theology)

 Christian Use of the Alphabet

 St. Alphonsus Liguori

 St. Alphonsus Rodriguez

 Prospero Alpini

 Alsace-Lorraine

 Diego Francisco Altamirano

 Altamura and Acquaviva

 Altar (in Liturgy)

 Altar (in the Greek Church)

 Altar (in Scripture)

 History of the Christian Altar

 Bl. Altmann

 St. Alto

 Diocese of Alton

 Diocese of Altoona

 Altruism

 Alumnus

 Niccolò Alunno

 Fernando Alvarez de Toledo, Duke of Alva

 Pedro d'Alva y Astorga

 Alonzo de Alvarado

 Fray Francisco de Alvarado

 Pedro de Alvarado

 Balthazar Alvarez

 Diego Alvarez

 Manoel Alvarez

 Alvarez de Paz

 St. Alypius

 José Antonio Alzate

 Johann Baptist Alzog

 Ama

 Giovanni Antonio Amadeo

 Dioceses of Amadia and Akra

 Amalarius of Metz

 St. Amalberga (1)

 St. Amalberga (2)

 Amalec

 Archdiocese of Amalfi

 Amalricians

 Amalricus Augerii

 St. Amandus

 Amasia

 Amastris

 Thaddeus Amat

 Amathus

 Diocese of Amazones

 Peter Ambarach

 Ambition

 Ambo

 Ambo (in the Russian and Greek Church)

 George d'Amboise

 Our Lady of Ambronay

 August Wilhelm Ambros

 St. Ambrose

 St. Ambrose of Camaldoli

 Bl. Ambrose of Sienna

 Ambrosian Basilica

 Ambrosian Chant

 Ambrosian Hymnography

 Ambrosian Library

 Ambrosian Liturgy and Rite

 Ambrosians

 Ambrosiaster

 Ambulatory

 Diocese of Amelia

 Denis Amelote

 Amen

 Amende Honorable

 Veit Amerbach

 America

 Pre-Columbian Discovery of America

 American College in Rome

 American College at Louvain

 South American College

 American Protective Association

 Francis Kerril Amherst

 Ven. John Amias

 Amice

 Antonio Amico

 Francesco Amico

 Diocese of Amida

 Diocese of Amiens

 Joseph Maria Amiot

 Amisus

 Daniel Ammen

 St. Ammon

 Ammon

 Ammonian Sections

 Ammonites

 Amorbach

 Amorios

 Amorrhites

 Eusebius Amort

 Amos

 Amovibility

 Vicariate Apostolic of Amoy

 André Marie Ampère

 Amphilochius of Iconium

 Amphilochius of Sida

 Amphoræ

 Abbey of Ampleforth

 Ampullæ

 Diocese of Ampurias

 Amra

 Amrah

 Amraphel

 Amsterdam

 Amulet

 Use and Abuse of Amulets

 Amyclae

 Jacques Amyot

 Anabaptists

 Pope St. Anacletus

 Anacletus II

 Anæsthesia

 Diocese of Anagni

 Analogy

 Analysis

 Anaphora

 Anarchy

 St. Anastasia

 Anastasiopolis

 St. Anastasius (1)

 Pope St. Anastasius I

 Pope Anastasius II

 Pope Anastasius III

 Pope Anastasius IV

 St. Anastasius (2)

 St. Anastasius Sinaita

 Anathema

 Anathoth

 St. Anatolia

 St. Anatolius (1)

 St. Anatolius (2)

 Anatomy

 Anazarbus

 Pedro de Añazco

 Joseph Anchieta

 Anchor

 Anchorites

 Ancient of Days

 Ancilla Dei

 Ciriaco d'Ancona

 Diocese of Ancona and Umana

 Ancren Riwle

 Ancyra

 Councils of Ancyra

 Andalusia

 William Henry Anderdon

 Anthony Maria Anderledy

 Henry James Anderson

 Lionel Albert Anderson

 Patrick Anderson

 James Anderton

 Ven. Robert Anderton

 Roger Anderton

 Thomas Anderton

 Heinrich Bernhard, Freiherr von Andlaw

 Ven. William Andleby

 Alonso Andrada

 Antonio de Andrada

 Diego Andrada de Payva

 Bernard André

 Yves Marie André

 Giovanni d'Andrea

 Bl. Andrea Dotti

 Andrea Pisano

 Andreas of Ratisbon

 Felix de Andreis

 Juan Andres

 St. Andrew (1)

 St. Andrew (2)

 St. Andrew Avellino

 Bl. Andrew Bobola

 St. Andrew Corsini

 Andrew of Caesarea

 St. Andrew of Crete

 Andrew of Lonjumeau

 Andrew of Rhodes

 St. Andrew the Scot

 William Eusebius Andrews

 Diocese of Andria

 Anemurium

 Felice Anerio

 Giovanni Francesco Anerio

 Filippo Anfossi

 Ange de Saint Joseph

 Ange de Sainte Rosalie

 Angel

 St. Angela Merici

 Bl. Angela of Foligno

 Francesco degli Angeli

 Girolamo degli Angeli

 Angelicals

 Fra Angelico

 Bl. Angelo Carletti di Chivasso

 Angelo Clareno da Cingoli

 Early Christian Representations of Angels

 Angels of the Churches

 Angelus

 Angelus Bell

 Angelus Silesius

 Anger

 Diocese of Angers

 University of Angers

 Notre Dame des Anges

 St. Angilbert

 Francesco Angiolini

 Priory of Anglesea

 Anglican Orders

 Anglicanism

 Timothy Warren Anglin

 Anglo-Saxon Church

 Anglona-Tursi

 Angola and Congo

 Diocese of Angora

 Diocese of Angoulême

 Diocese of Angra

 Pedro Angulo

 Vicariate Apostolic of Anhalt

 Pope St. Anicetus

 College and Church of the Anima (in Rome)

 Anima Christi

 Animals in Christian Art

 Animals in the Bible

 Animism

 Giovanni Animuccia

 Anise

 Anna

 Anna Comnena

 Ecclesiastical Annals

 Annas

 François Annat

 Annates

 St. Anne

 Sainte Anne d'Auray

 Sainte Anne de Beaupré

 Diocese of Annecy

 Joseph Annegarn

 Annibale d'Annibaldi

 Giuseppe d'Annibale

 Annius of Viterbo

 St. Anno

 Annunciation of the Blessed Virgin Mary

 Feast of the Annunciation of the Blessed Virgin Mary

 Orders of the Annunciation

 Louis-Pierre Anquetil

 Casto Innocenzio Ansaldi

 Giordano Ansaloni

 St. Anschar

 Councils of Anse

 Ansegisus

 St. Ansegisus

 St. Anselm (1)

 St. Anselm (2)

 Anselm of Laon

 Anselm of Liège

 St. Anselm of Lucca, the Younger

 Antoine Anselme

 Reyer Anslo

 Thomas Chisholm Anstey

 Antediluvians

 Pope St. Anterus

 Joseph Anthelmi

 Anthemius

 St. Anthony

 Orders of Saint Anthony

 St. Anthony of Padua

 Anthony of Sienna

 Anthony of the Mother of God

 Anthropomorphism

 Antichrist

 Antidicomarianites

 Antidoron

 Diocese of Antigonish

 Antimensium

 Antinoe

 Antinomianism

 Church of Antioch

 Antioch

 Antiochene Liturgy

 Antiochus of Palestine

 Antipater of Bostra

 Antipatris

 Antiphellos

 Antiphon

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Aachen, in French, Aix-la-Chapelle, the name by which the city is generally known; in Latin Aquæ Grani, later Aquisgranum, is the capital of a presidency in Rhenish Prussia, and lies in a valley basin, surrounded by wooded heights, on the Wurm, a tributary of the Roer, on its way to the Meuse. Population, 1 December, 1905, 151,922 (including the Parish of Forst); Catholics, 139,485; Protestants, 10,552; Israelites, 1,658; other denominations, 227. The city owes its origin to its salubrious springs which were already known in the time of the Romans. There appears to have been a royal court in Aachen under the Merovingians, but it rose to greater importance under Charlemagne who chose it as his favourite place of residence, adorned it with a noble imperial palace and chapel, and gave orders that he should be buried there.

The precious relics obtained by Charlemagne and Otho III for the imperial chapel were the objects of great pilgrimages in the Middle Ages (the so-called "Shrine Pilgrimages") which drew countless swarms of pilgrims from Germany, Austria, Hungary, England, Sweden, and other countries. From the middle of the fourteenth century onwards, however it became customary to expose the four great relics only once in every seven years, a custom which still holds. These pilgrimages, the coronations of the German emperors (thirty-seven of whom were crowned there between 813 and 1531), the flourishing industries and the privileges conferred by the various emperors combined to make Aachen one of the first cities of the Empire.

The decay of Aachen dates from the religious strife of the German Reformation. Albrecht von Muenster first preached Protestantism there in the year 1524 but was afterwards forbidden to preach the new views and executed on account of two murders committed during his stay in the cities of Maastricht and Wesel. A new Protestant community was soon, however formed in Aachen, which gradually attained such strength as to provoke a rising in 1581, force the election of a Protestant burgomaster, and defy the Emperor for several years. The Ban of the Empire was, therefore, pronounced against the city in 1597 and put in force by the Duke of Julich, the Catholic overlord of the city. The Catholics were restored to their rights, and the Jesuits invited to Aachen, in 1600. In 1611, however, the Protestants rose afresh, plundered the Jesuit college, drove out the Catholic officials in 1612, and opened their gates to troops from Brandenburg. The Ban of the Empire was again laid on the city, and executed by the Spanish general, Spinola. The Protestant ringleaders were tried or exiled, and many other Protestants banished. These troubles, together with a great fire which destroyed 4,000 houses, put an end to the prosperity of the city.

Two treaties of peace were concluded at Aachen during the seventeenth and eighteenth centuries. By the first, dated 2 May 1668, Louis XIV was compelled, by the Triple Alliance between England, the Netherlands, and Sweden, to abandon the war against the Spanish Netherlands, to restore the Franche Comté, which he had conquered, and to content himself with twelve Flemish fortresses. The second treaty, dated 18 October, 1748, put an end to the War of the Austrian Succession. In 1793 and 1794, Aachen was occupied by the French, incorporated with the French Republic in 1798 and 1802, and made the capital of the Department of the Roer. By the terms of the French Concordat of 1801 Aachen was made a bishopric subject to the Archbishop of Mechlin, and composed of 79 first class, and 754 second class, parishes. The first and only bishop was Marcus Antonius Berdolet (b. 13 September, 1740, at Rougemont, in Alsace 3; d. 13 August, 1809), who, for the most part, left the government of his diocese to his vicar-general, Martin Wilhelm Fonck (b. 28 October, 1752, at Goch; d. 26 June, 1830, as Provost of Cologne Cathedral). After the death of Bishop Berdolet the diocese was governed by Le Camus, Vicar General of Meaux; after his death, in 1814, by the two vicars-general Fonck and Klinkenberg. The Bull of Pius VII, "De Salute Animarum," dated 16 July, 1821 which regulated church matters in Prussia anew, did away with the bishopric of Aachen, and transferred most of its territory to the archdiocese of Cologne; a collegiate chapter, consisting of a provost and six canons, taking the place of the bishopric in 1825. In 1815 Aachen became Prussian territory. The Congress of Aix-la-Chapelle sat there from 30 September to 11 November, 1818, and was attended by the sovereigns of Russia, Austria, and Prussia, and by plenipotentiaries from France and England, to determine the relations between France and the Powers. France obtained a reduction of the war indemnity and the early departure of the army of occupation, and joined the Holy Alliance; the other four Powers guaranteed the throne of France to the Bourbons, against any revolution that might occur. Aachen, under Prussian government, returned to prosperity, chiefly through the development of the coal mines in the neighborhood, which facilitated several extensive industries (such as the manufacture of linen, needles, machinery, glass, woolen, and half-woollen stuffs, etc.), but also in consequence of the large number of visitors to its hot springs.

Ecclesiastically, Aachen constitutes a deanery of the archdiocese of Cologne. It has a collegiate chapter, already mentioned, with a provost, six regular and four honorary, canons; 12 Catholic parishes, 46 Catholic churches and chapels; in 1906, there were 87 secular, and 24 regular, clergy, besides 9 priests from other dioceses. The minster ranks first among the church buildings; it consists of three distinct parts: the octagon, the choir, and the crown, or ring, of chapels, the octagon forming the central portion. This last is the most important monument of Carlovingian architecture; it was built between 796 and 804, in the reign of Charlemagne, by Master Odo of Metz, and modeled after the Italian circular church of San Vitale at Ravenna. It was consecrated by Pope Leo III. It is an eight-angled, domed building, 54 feet in diameter, with a sixteen-sided circumference of 120 feet, and a height of 124 feet. The interior of the dome is adorned with mosaics on a gold ground, executed by Salviati of Venice, in 1882, representing Our Lord surrounded by the four and twenty Ancients of the Apocalypse. The main building was decorated with marble and mosaics in 1902 after the designs of H. Schaper. Over the spot supposed to be the site of Charlemagne's grave hangs an enormous corona of lamps, the gift of the Emperor Frederick I, Barbarossa; in the choir of the octagon, the so-called upper minster, stands Charlemagne's throne, made of great slabs of white marble, where, after the coronation, the German emperors received the homage of their nobles. The rich upper choir, built in Gothic style, joins on to the eastern side of the octagon; it was begun in the second half of the fourteenth century, and dedicated in 1414. The thirteen windows, each 100 feet high, have been filled with new colored glass; on the pillars between them stand fourteen statues (the Mother of God, the Twelve Apostles, and Charlemagne), dating from the fifteenth century. Among the treasures of the choir should be mentioned the famous Gospel-pulpit, enriched with gold plates, the gift of the Emperor Henry II, the throne canopy of the fifteenth century, the new Gothic high altar of 1876, and the memorial stone which marks the spot where the Emperor Otto III formerly lay. The lower portions of the bell tower, to the west of the octagon, belong to the Carlovingian period; the Gothic superstructure dates from 1884. Of the chapels which surround the whole building, the so-called Hungarian chapel contains the minster treasury, which includes a large number of relics, vessels, and vestments, the most important being those known as the four "Great Relics." namely, the cloak of the Blessed Virgin, the swaddling clothes of the Infant Jesus, the loincloth worn by Our Lord on the Cross, and the cloth on which lay the head of St. John the Baptist after his beheading. They are exposed every seven years, and venerated by thousands of pilgrims (139,628 in 1874, and 158,968 in 1881). Among the other Catholic churches of Aachen, the following may be mentioned: the Church of Our Lady, a Gothic church in brick, built by Friederich Statz in 1859; the Church of St. Foillan, the oldest parish church in the city, which dates, in its present form, from the Gothic period, and was renovated between 1883 and 1888; and the Romanesque Church of St. James, built between 1877 and 1888. The most important secular building is the Rathaus, built between 1333 and 1350, on the site of, and out of the ruins of, Charlemagne's imperial palace, and completely renovated between 1882 and 1903. The facade is adorned with the statues of fifty-four German emperors, the great hall (Kaisersaal) with eight frescoes from designs by Alfred Rethel.

In Aachen there are foundations established by the Franciscans, Capuchins, and Redemptorists. The Alexians have one institution, a sanatorium and hospital for insane men and epileptics. The Franciscan Brothers conduct an apprentices' home and an asylum for boys. A number of female orders also have establishments. The Sisters of St. Charles Borromeo have charge of an eye hospital, a city asylum for orphans and the aged, with a wing for insane women, and Our Lady's Hospital, a working-women's home, and a protectory for girls. The Christensians have but one house, which is devoted to the care of the sick. The Sisters of St. Elizabeth have five: a motherhouse, a city hospital of St. Vincent, a city home for the sick, an asylum for the aged poor under the patronage of St. Joseph, and a city hospital of Our Lady of Help. The Franciscan Sisters have six institutions: a motherhouse, a refuge for working-women, an asylum for homeless girls, a home for servant-girls out of employment and domestics no longer able to work, a hospital of St. Mary, and a sanatorium. The Sisters of the Good Shepherd have one house. The Sisters of the Poor Child Jesus conduct two: a school for neglected girls, with a manual-training school and kindergarten attached, and a hospital and sanatorium for members of the Society, with a boarding house, eight shelters, etc. The Carmelites have one institution, and the Ursulines one, a higher boarding school for girls. The Sisters of St. Vincent have a crèche and two kindergartens, besides six Catholic orphanages. Among the religious and social unions should be mentioned eight congregations and two unions for boys, one workmen's union, one journeymen's union with a home of its own, two tradesmen's unions, one union of female shop-employees, the Catholic Protective Union for girls, women, and children, one vestment society, and one Cecilian society. There are two Catholic daily papers published in Aachen.

Councils of Aachen.—A number of important councils were held here in the early Middle Ages. In the mixed council of 789, Charlemagne proclaimed an important capitulary of eighty-one chapters, largely a repetition of earlier ecclesiastical legislation, that was accepted by the clergy and acquired canonical authority. At the council of 799, after a discussion of six days, Felix, Bishop of Urgel, in Spain, avowed himself overcome by Alcuin and withdrew his heretical theory of Adoptianism. In the synods of 816, 817, 818, and 819, clerical and monastic discipline was the chief issue, and the famous "Regula Aquensis" was made obligatory on all establishments of canons and canonesses (see Monasticism, Western), while a new revision of the Rule of St. Benedict was imposed on the monks of that order by the reformer Benedict of Aniane. The synod of 836 was largely attended and devoted itself to the restoration of ecclesiastical discipline that had been gravely affected by the civil wars between Louis the Pious and his sons. From 860 to 862 three councils were occupied with the question of the divorce of King Lothaire I from his wife, Theutberga. In 1166 took place the famous schismatic council, approved by the Antipope Paschal III, in which was decreed the canonization of Charlemagne, that was solemnly celebrated 29 December of that year.