Religious Orders were soon established in the diocese, including the Dominicans in 1246, and the Franciscans sometime between 1473-79.

Until the fifteenth-century, Scotland had no archbishop.

Although Pope Alexander III had recognised Glasgow as 'Specialis Filia Romanae Ecclesiae'(Special Daughter of the Roman Church), a direct relationship extended by Pope Celestine III to the entire Scottish Church, York repeatedly claimed to have jurisdiction in Scotland.

St. Andrews became an archdiocese in 1472. Supported by the Scottish King and Parliament, Glasgow campaigned for, and received in 1492, similar recognition. The first archbishop was Robert Blacader. During his episcopate, work was begun on the Blacader aisle in the medieval Cathedral.

Blacader’s prayer-book, now in the National Library of Scotland, represents the religious and artistic vitality of the late medieval church.

For the care of the sick, a leper hospital, dedicated to St.Ninian, continued to function in the Gorbals district.

One of Blacader’s successors, Gavin Dunbar, was involved in the developments leading to the endowment of the College of Justice (Court of Session) in 1532. But Dunbar’s feuding with the Beaton family further damaged the Church in already difficult times.

Archbishop James Beaton, consecrated in 1552, died in exile in Paris in 1603, the last surviving member of the pre-Reformation Scottish hierarchy. He had left Scotland carrying many of the Church’s precious documents, hoping to save them from the ravages that were to come following Knox’s Confession of Faith in 1560.

Glasgow did not figure prominently in the post-Reformation history of the Scottish Catholic community, apart from the martyrdom of John Ogilvie in 1615 - an unusually severe punishment. The more normal sentence for priests apprehended in Scotland was banishment.

Catholicism survived in the western Highlands and Islands, and in areas of north-eastern Scotland such as the Enzie district of Banffshire.

In 1694 the status of the Catholic Church in Scotland was enhanced by the appointment of a Vicar Apostolic to oversee the progress of the Church. Later, a new administrative structure was established in 1827 when Scotland was divided into three vicariates, with Glasgow as the centre of a new Western District.

The re-emergence of Catholicism in Glasgow must be attributed to Highland migrants, as well as to the larger number of Irish immigrants. During the 19th and 20th centuries, other immigrants too would arrive, from Italy, Germany, Holland, Belgium, Lithuania, and Poland.

In 1780, a priest would occasionally come from Drummond Castle near Crieff in Perthshire to celebrate Mass for the small number of Catholics in the city, but not until 1792 would Glasgow have its first resident priest, Alexander McDonell.

He was succeeded by Rev John Farquharson in 1795, and by Rev Andrew Scott in 1805.

It was Andrew (later Bishop) Scott who undertook the building of St.Andrew's church (now Cathedral) on the banks of the Clyde, though not without some misgivings as to the financial burdens it might impose on the Catholic community.

Building work began in 1814, and the new permanent church was opened in December 1816.

Meanwhile, the establishment of regular steamboat services contributed to a steady influx of immigrants from Ireland. The growth in Catholic numbers did not pass unnoticed. Kirkman Finlay, the city's MP, encouraged the beginnings of Catholic education as early as 1817.

Some reaction was overtly hostile, with complaints being made that the migrants were a burden on the system of poor relief. The church itself, through the efforts of the St.Vincent de Paul Society and the Religious Orders, set up a variety of social welfare institutions including an orphanage (initially in Calton, but later at Smyllum House in Lanark), a children's refuge, and a home for the elderly. Religious Orders also helped in the staffing of schools.

In parishes, agencies like the League of the Cross encouraged temperance from alcohol, while parochial savings banks encouraged the twin Victorian virtues of thrift and self-help.

Pending the restoration of the hierarchy, Mgr Charles Eyre from the Diocese of Hexham and Newcastle was appointed titular Archbishop of Anazarbus and Apostolic Delegate to Scotland in 1868, and Apostolic Administrator of the Western District the following year. He subsequently became the first post-Reformation Archbishop of Glasgow when Leo XIII restored the Scottish Hierarchy in 1878.

By 1877, a year prior to the restoration of the Hierarchy, Archbishop Charles Eyre could record that in Glasgow city there were nineteen parishes, served by fifty-two priests, and in the county of Dunbarton, five parishes and seven priests.

Lanarkshire, which became Motherwell diocese in 1947-48, had seventeen parishes and twenty-two priests, while Renfrewshire, which became Paisley diocese in 1947-48, had eleven parishes and sixteen priests.

In 1888, Celtic Football Club was established as a means of raising money to fund 'the Poor Children's Dinner Tables' of the East End parishes of St.Mary's, Sacred Heart, and St.Michael's.

To train clergy, Archbishop Eyre founded St.Peter's College at Partickhill in 1874, and also encouraged the opening at Dowanhill in 1894 of Notre Dame teacher-training college. He was also committed to creating new parishes and breaking up over-large ones which he felt 'were almost dioceses in themselves'.

During the episcopate of his successor, Archbishop John Maguire, the Education (Scotland) Act (1918) was passed. Financial difficulties, including the triple burden of salaries, building costs, and rising educational expectations necessitated a settlement.

Maguire also firmly supported the War effort of 1914-18. In 1917, soldier-students went to the Front from St.Peter's College, and two of the military chaplains from the Archdiocese were killed. Although the seminary never closed during the First World War, at one point it housed only a single student and the rector.

The provision of education, and social services in particular, brought the Catholic community into wider contact with society, in the form of Government, and School, and Poor Law, Boards. In the 19th and early 20th centuries, the Catholic Union sought to maximise the Catholic vote at elections, but by the 1940s it had been superseded as it became more difficult to isolate uniquely Catholic political issues and Catholics were steadily drawn into national life.

In 1925, Archbishop Mackintosh founded a chaplaincy at the University (now Turnbull Hall) for the increasing number of Catholic students. In such wider contacts began a process of ecumenical understanding which led to the formation in 1991 of 'Glasgow Churches Together'.

City placenames, such as Blackfriars Street, St.Rollox/St.Roch, and the presence into the 20th century of religious orders such as the Franciscans and Dominicans are tangible links with the medieval past.

Hospices and care services continue the long tradition dating back to medieval times of concern for the most disadvantaged in the community.

In spite of all the vagaries of history, both city and Church still acknowledge their common links with Mungo: Glasgow’s Patron, Glasgow’s Saint.