The Catholic Evidence Guild is a loose international association of Roman Catholic lay volunteers which seeks to research and present clear and compelling explanations of the doctrine of the Roman Catholic Church.
 The organisation was founded in the Diocese of Westminster, England towards the end of 1918.
 By 1925 there were 20 to 30 branches throughout England.
 The Westminster branch has spoken regularly at Speakers' Corner since its inception.
 Prospective speakers were put through a strict training system by the Guild, with the goal of enabling "the ordinary Catholic to explain the truths of his religion in such a way as to reach the understanding of the crowd."
Protestantism is a branch of the monotheistic Christian religion which originated in Europe in the early 16th Century AD/CE.
 It adheres doctrinally to the doctrine of the Holy Trinity and other theological doctrines of the Catholic Church and the Eastern Orthodox Church, but split from the Western (Roman) Catholic Church as a "Protest" against ecclesiastical corruption, pastoral abuses and certain doctrines of the Roman Catholic Church.
 Protestantism itself had multiple variations from the start, specifically among followers of Martin Luther, John Calvin, Huldrych Zwingli and later, Thomas Cranmer.
Bishop of Clonmacnoise was the ordinary of the Roman Catholic episcopal see based at Clonmacnoise, County Offaly, Ireland.
 The bishops of Clonmacnoise (Old Irish: "Cluain Moccu Nóis") appear in the records for the first time in the 9th century, although inferior in status to the Abbot of Clonmacnoise until the reformation of the Irish Church in the 12th century.
 After the Reformation, there were several parallel bishops placed by the Church of Ireland until the Diocese of Clonmacnoise was merged with Diocese of Meath to form the Diocese of Meath and Kildare in 1569.
 In the Roman Catholic Church, separate bishops continued longer.
 The diocese came under the administration of the Bishop of Ardagh between 1688 and 1725, before the provision of Stephen MacEgan in 1725.
 Although MacEgan was translated to Meath in 1729, he continued to administer Clonmacnoise separately until his death in 1756, after which the see was finally merged into the Roman Catholic Diocese of Ardagh and Clonmacnoise.
St. Anne's Church, in Biała Podlaska, Poland is a Baroque Roman Catholic church.
 It was originally built in 1572, on the site of an earlier shrine, as a Protestant church dedicated to the Arianism doctrine.
 The Protestants were expelled in 1596 by Mikołaj Krzysztof "the Orphan" Radziwiłł.
 Between 1597-1603 it was rebuilt as a Catholic church, being dedicated to Saint Anne in 1603.
 The church is built in the shape of a Latin cross.
The Roman Catholic dioceses in Great Britain are organised by two separate hierarchies: the Roman Catholic Church in England and Wales, and the Roman Catholic Church in Scotland.
 Within Great Britain, the Roman Catholic Church of England and Wales has five provinces, subdivided into 22 dioceses, and the Roman Catholic Church of Scotland has two provinces, subdivided into 6 dioceses.
 The Roman Catholic dioceses in Northern Ireland are organised together with those in the Republic of Ireland, as the Church in Ireland was not divided when civil authority in Ireland was partitioned in the 1920s.
The Roman Inquisition, formally the Supreme Sacred Congregation of the Roman and Universal Inquisition, was a system of tribunals developed by the Holy See of the Roman Catholic Church, during the second half of the 16th century, responsible for prosecuting individuals accused of a wide array of crimes relating to religious doctrine or alternate religious doctrine or alternate religious beliefs.
 In the period after the Medieval Inquisition, it was one of three different manifestations of the wider Catholic Inquisition along with the Spanish Inquisition and Portuguese Inquisition.
The ministerial orders of the Roman Catholic Church (for similar but different rules among Eastern Catholics see Eastern Catholic Church) are those of bishop, presbyter (more commonly called priest in English), and deacon.
 The ordained priesthood and the common priesthood (or priesthood of all the baptized faithful) are different in function and essence.
 The Catholic Church teaches that when a man participates in priesthood, he participates in the priesthood of Christ Himself.
 All men who, through the Sacrament of Holy Orders, have become priests participate in Christ's priesthood; they act "in persona Christi Capitis", in the person of Christ, the Head of His Body, the Church.Unlike usage in English, "the Latin words "sacerdos" and "sacerdotium" are used to refer in general to the ministerial priesthood shared by bishops and presbyters.
 The words "presbyter", "presbyterium" and "presbyteratus" refer to priests in the English use of the word or presbyters."
 According to the "Annuario Pontificio" 2016, as of December 31, 2014, there were 415,792 Catholic priests worldwide, including both diocesan priests and priests in the religious orders.
 A priest of the regular clergy is commonly addressed with the title "Father" (abbreviated Fr., in the Roman Catholic and some other Christian churches).
The Corporal of Bolsena dates from a Eucharistic miracle in Bolsena, Italy, in 1263 when a consecrated host allegedly began to bleed onto a corporal, the small cloth upon which the host and chalice rest during the Canon of the Mass.
 The appearance of blood was seen as a miracle to affirm the Roman Catholic doctrine of transubstantiation, which states that the bread and wine become the Body and Blood of Christ at the moment of consecration during the Mass.
 Today the Corporal of Bolsena is preserved in a rich reliquary at Orvieto in the cathedral.
 The reddish spots on the cloth, upon close observation, show the profile of a face similar to those that traditionally represent Jesus Christ.
 It is said that the miraculous bleeding of the host occurred in the hands of an officiating priest who had doubts about transubstantiation.
 The "Miracle of Bolsena" is regarded by the Roman Catholic Church as a private revelation, meaning that Catholics are under no obligation to believe it although they may do so freely.
The Bonn Agreement of 1931 is a document, negotiated on 2 July 1931 in Bonn, which established full communion between the Church of England and the Old Catholic churches of the Union of Utrecht, including the Old Catholic Church of the Netherlands.
 This full communion has since been extended to all churches of the Anglican Communion through their synods.
The term Old Catholic Church was originally used from the 1850s by groups which had separated from the Roman Catholic Church over certain doctrines, primarily concerned with papal authority.
 These churches are not in full communion with the Roman Catholic Church.
 Member churches of the Union of Utrecht of the Old Catholic Churches (UU) are in full communion with the Anglican Communion, and some are members of the World Council of Churches.

Question: Why did the Roman catholic church become separate over which doctrine?
Answer: papal authority