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United Dioceses of Dublin and Glendalough
Dioeceses Unitae Dublinensis et Glendalochensis
Deoisí Aontaithe Bhaile Átha Cliath agus Ghleann Dá Loch
|Cathedral||Christ Church Cathedral, Dublin|
|Bishop||Michael Jackson, Archbishop of Dublin and Bishop of Glendalough|
The United Dioceses of Dublin and Glendalough is a diocese of the Church of Ireland in the east of Ireland. It is headed by the Archbishop of Dublin, who is also styled the Primate of Ireland. The diocesan cathedral is Christ Church Cathedral, Dublin.
The broad Dublin area was Christian long before Dublin had a distinct diocese, with monasteries such as Glendalough as well as at Finglas, Glasnevin, Rathmichael, Swords, Tallaght. Several of these functioned as "head churches" and the most powerful of all was Glendalough.
In the early church in Ireland, the church had a monastic basis, with greatest power vested in the Abbots of the major communities. There were bishops but not organised dioceses in the modern sense, and the offices of abbot and bishop were often comprised in one person. Some early "Bishops of Dublin", back to 633, are mentioned in Ware's Antiquities of Ireland but the Diocese of Dublin is not considered to have begun until 1038, and when Ireland began to see organised dioceses, all of the current Diocese of Dublin, and more, was comprised in the Diocese of Glendalough.
Following a reverted conversion by one Norse King of Dublin, Sitric, his son Godfrey became Christian in 943, and the Kingdom of Dublin first sought to have a bishop of its own in the 11th century, under Sitric MacAulaf, who had been on pilgrimage to Rome. He sent his chosen candidate, Donat (or Donagh or Donatus), to be consecrated in Canterbury in 1038, and the new prelate set up the Diocese of Dublin as a small territory within the walled city, over which he presided until 1074. The new diocese was not part of the Church in Ireland but of the Norse Province of Canterbury. Sitric also provided for the building of Christ Church Cathedral in 1038 "with the lands of Baldoyle, Raheny and Portrane for its maintenance." 
At the Synod of Rathbreasail, convened in 1118 by Gillebert (Gilbert), Bishop of Limerick, on papal authority, the number of dioceses in Ireland was fixed at twenty-four. Dublin was not included, the city being described as lying in the Diocese of Glendalough, but the Norse Bishops continued, still attached to Canterbury.
Then, in 1151, Pope Eugene III commissioned Cardinal Paparo to go to Ireland and establish four metropolitans, and at a general synod at Kells in 1152, Armagh, Dublin, Cashel, and Tuam, were created archiepiscopal sees. In a document drawn up by the then Archbishop of Tuam in 1214, the cardinal is described as finding both a bishop based in Dublin, who at the time exercised his episcopal office within the city walls only, and "He found in the same Diocese another church in the mountains, which likewise had the name of a city (Glendalough) and had a certain chorepiscopus. But he delivered the pallium to Dublin which was the best city and appointed that the diocese (Glendalough) in which both these cities were should be divided, and that one part thereof should fall to the metropolitan."
The part of North County Dublin known as Fingall was taken from Glendalough Diocese and attached to Dublin City. The new Archdiocese had 40 parishes, in deaneries based on the old senior monasteries. All dependence upon English churches such as Canterbury was also ended.
The founding Archbishop of the larger Dublin Diocese, consecrated at Lambeth, was Gregory, with the Bishops of Kildare, Ossory, Leighlin, Ferns, and Glendalough reporting to him.
The second Archbishop, from 1161 to 1179, was Saint Laurence O'Toole, previously Abbot of Glendalough, who had previously been elected as Bishop of Glendalough but had declined that office. During his time in office, the presence of the Church grew in Dublin city (by 1170 there were six churches other than the cathedral within the walls  ) and religious orders from the continent came to Ireland (Augustinians, Dominicans, Franciscans and Carmelites had houses in Dublin, and the great convent of Grace Dieu, near Donabate, was an example of women's religious life and education). As part of this trend, Laurence installed a community of canons to minister according to the Aroasian Rule in the Cathedral of the Holy Trinity, later known as Christchurch. The important house of Abbey of Saint Mary was founded in Dublin at that time, first under the Benedictine Rule, then passing to the Cistercians.
Not only was the Irish Church transformed in that 12th century by new organisation and new arrivals from abroad, but Ireland's political scene was changed permanently by the coming of the Normans and the influence of the English Crown.
Saint Laurence's successor was a Norman, and from then onward to the time of the Reformation in Ireland, Dublin's Archbishops were all either Norman or English.
In 1185, the Lord of Ireland, John Lackland, granted the merger of the dioceses of Dublin and Glendalough. This was initially without effect as the charter lacked papal approval. When the bishop Macrobius died in 1192, a synod was held in Dublin under the direction of the papal legate Metthew O Enna. William Piro was elected as bishop of Glendalough and remained in office at least until 1212. Robert de Bedford was elected as successor in 1213 or 1214 but he had never the opportunity to take possession of the diocesan seat. Instead, John, now King of England, reissued a grant to join Glendalough to Dublin which was finally approved by Pope Innocent III in 1216 and confirmed by his successor Honorius III in the same year.  
When the Church in England broke communion with the Roman Catholic Church, the Church of England was established by the state as the established church. Later, by decree of the Irish Parliament, a similar new body became the State Church in the Kingdom of Ireland. It assumed possession of most Church property (and so retained a great repository of religious architecture and other items, though some were later destroyed). The substantial majority of the population remained faithful to the Latin Rite of Roman Catholicism, despite the political and economic advantages of membership in the state church. They were obliged to find alternative premises and to conduct their services in secret. The English-speaking minority mostly adhered to the Church of Ireland or to Presbyterianism. In 1833, the two provinces of Dublin and Cashel were merged. Over the centuries, numerous dioceses were merged, in view of declining membership.
The united entity comprises 95 parishes, many now operating in unions. The parishes and other religious organisations in diocesan jurisdiction include:
Saint Patrick's Cathedral in Dublin, Ireland, founded in 1191, is the national cathedral of the Church of Ireland. Christ Church Cathedral, also a Church of Ireland cathedral in Dublin, is designated as the local cathedral of the Diocese of Dublin and Glendalough.
Christ Church Cathedral, more formally The Cathedral of the Holy Trinity, is the cathedral of the United Dioceses of Dublin and Glendalough and the cathedral of the ecclesiastical province of the United Provinces of Dublin and Cashel in the (Anglican) Church of Ireland. It is situated in Dublin, Ireland, and is the elder of the capital city's two medieval cathedrals, the other being St Patrick's Cathedral.
Lorcán Ua Tuathail, known in English as Laurence O'Toole and in French as Laurent d'Eu, was Archbishop of Dublin at the time of the Norman invasion of Ireland. Lorcán played a prominent role in the Irish Church Reform Movement of the 12th century and mediated between the parties during and after the invasion. He was canonised in 1225 by Pope Honorius III.
The Synod of Ráth Breasail was an Irish Catholic church council which took place in Ireland in 1111. It marked the transition of the Irish church from a monastic to a diocesan and parish-based church. Many Irish present day dioceses trace their boundaries to decisions made at the synod.
The United Provinces of Dublin and Cashel, commonly called the Province of Dublin, and also known as the Southern Province, is one of the two ecclesiastical provinces that together form the Church of Ireland; the other is the Province of Armagh. The province has existed since 1833 when the ancient Province of Dublin was merged with the Province of Cashel. Its metropolitan bishop is the Archbishop of Dublin.
John Robert Winder Neill was the Church of Ireland Archbishop of Dublin until the end of January 2011.
Cellach of Armagh or Celsus or Celestinus (1080–1129) was Archbishop of Armagh and an important contributor to the reform of the Irish church in the twelfth century. He is venerated in the Roman Catholic Church as Saint Cellach. Though a member of the laicised ecclesiastical dynasty of Clann Sínaig, he took holy vows and gained priestly ordination. This put an end to the anomalous state of affairs, in effect since 966, whereby the supreme head of the Irish Church had been a layman. Following the Synod of Ráith Bressail, in which a diocesan structure for Ireland was established, he became the first metropolitan primate of all Ireland.
The Synod of Kells took place in 1152, under the presidency of Giovanni Cardinal Paparoni, and continued the process begun at the Synod of Ráth Breasail (1111) of reforming the Irish church. The sessions were divided between the abbeys of Kells and Mellifont, and in later times the synod has been called the Synod of Kells-Mellifont and the Synod of Mellifont-Kells.
The Archdiocese of Dublin is an ecclesiastical territory or archdiocese of the Catholic Church located in the eastern part of Ireland. Its archepiscopal see includes the republic's capital city – Dublin. The cathedral church of the archdiocese is St Mary's Pro-Cathedral. Dublin was formally recognised as a metropolitan province in 1152 by the Synod of Kells. Its second archbishop, Lorcán Ua Tuathail, is also its patron saint.
The Parish of Taney is a populous parish in the Church of Ireland, located in the Dundrum area of Dublin.
Coolock is an ecclesiastical parish of the Church of Ireland located in Dublin, Ireland. It is one of two successors to the ancient parish of that name, the other being the ongoing Roman Catholic parish of St Brendan.
St Brendan's is a parish in Coolock, Dublin in Ireland that is served by the Church of St Brendan. The parish is in the Fingal South East deanery of the Roman Catholic Archdiocese of Dublin. The parish is based on the civil parish of Coolock. During penal times, it was one of the few functioning Catholic parishes in Dublin.
Founded in the early days of Irish Christian parish structures, the Parish of Clontarf assumed in 1829 the mantle of Union Parish for a large area of north Dublin, Ireland, a role previously filled by the Parish of Coolock, into which Clontarf had been subsumed in 1614 - refer to that article for history from 1618 to 1879. Clontarf itself is a large northside suburb of Dublin, and the parish was in the 20th century divided into the modern parishes which now serve that area.
The Archbishop of Dublin is a senior bishop in the Church of Ireland, second only to the Archbishop of Armagh. The archbishop is the diocesan bishop of the United Dioceses of Dublin and Glendalough and the metropolitan bishop of the Province of Dublin, which covers the southern half of Ireland, and he is styled Primate of Ireland.
The Parish of Raheny is the modern successor in the Roman Catholic Church to an early (1152) parish, in Raheny, a district of Dublin, Ireland, reputed to be a site of Christian settlement back to at least 570 A.D. Today's parish, within the Howth Deanery of the Roman Catholic Archdiocese of Dublin, comprises Raheny village and the central portion of the district, parts of which are also served by the parishes of Killester, Grange Park and Kilbarrack-Foxfield. The parish has a membership of around 10,000 Catholics. Similarly centred, and covering a greater land area but a much smaller membership, is the Church of Ireland parish of the same name.
The Parish of Raheny is the modern successor in the Church of Ireland to an early (1152) parish, in Raheny, a district of Dublin reputed to be a site of Christian settlement back to 570. Today's parish comprises Raheny village and the wider district, and is in a Union with the Parish of Coolock. Its parish church is All Saints' Church, Raheny.
The Archbishop of Dublin is the title of the senior cleric who presides over the Archdiocese of Dublin. The Church of Ireland has a similar role, heading the United Dioceses of Dublin and Glendalough. In both cases, the Archbishop is also Primate of Ireland. The Archbishop has his seat at Saint Mary's Pro-Cathedral, though formally Dublin's cathedral is still Christchurch Cathedral, Dublin as recognised by the Holy See. From 29 December 2020 until 2 February 2021, the position had been vacant, as Diarmuid Martin having resigned after turning 75, as canon law required of him. Dermot Farrell was installed as the new Archbishop of Dublin on 2 February 2021.
Dúnán was the first bishop of Dublin, appointed under Dublin's Hiberno-Norse kings. He is known also as Donatus or Donat. The diocese was put on a regular basis, in 1028, at the request of Sigtrygg Silkbeard. In his obit in the Annals of Ulster Dúnán is described as "chief bishop of the foreigners".
The Archbishop of Dublin is an archiepiscopal title which takes its name after Dublin, Ireland. Since the Reformation, there have been parallel apostolic successions to the title: one in the Catholic Church and the other in the Church of Ireland. The archbishop of each denomination also holds the title of Primate of Ireland.