Reformation
 
Between the 12th and 15th centuries, the Church in Scotland thrived. There were thirteen dioceses (compared to eight today) and mass was celebrated in every corner of the Scottish Kingdom. Such was the strength of anti-Catholic feeling during the Scottish Reformation that, within a single generation, Scotland changed from being a Catholic country to being one where practising the Catholic faith was an offence punishable by death. In the seventy years between 1546 and 1615, a Cardinal, an Archbishop and three priests were hanged for heresy. Papal authority was abolished by law and Parliament decreed that all monasteries and abbeys should be destroyed. By 1611 only four priests were to be found in the whole country. In 1696 all existing Scottish Catholics were ordered to leave Scotland.The oppression of Catholics in Scotland continued with varying degrees of intensity until The Catholic Emancipation Act was passed in 1827. The subjugated Catholic population had been ministered to by a series of devoted priests and, as times became less intolerant, Scotland was divided into three large districts - the Northern, Eastern and Western vicariates.
 
On 30th November 1830, a group of twelve devout Catholic men gathered in Torrance, near Lennoxtown to draft a letter to Bishop Andrew Scott, coadjutor of the Western District and to Bishop Paterson of the Eastern, begging both their Lordships to find a priest for their community 'as their are a great number of Roman Catholics here.' They were aware that although the nearest place of worship to them was in Glasgow, in fact they came under the jurisdiction of the Eastern District. The appeal was successful and 1831 saw the establishment of St Paul's Mission in Lennoxtown. The church building was completed in 1846 and in 1881 permission was granted to change the name to St Machan in honour of the ancient local Scottish saint.
 
1846 was also the year that saw the start of the Irish Potato Famine. A million and a half men, women and children were forced to leave their native home in the decade that followed. Many thousands settled in Scotland bringing with them their devotion to the Catholic Church. The immigrants found employment in ironstone and coalmining, in limestone working, in iron and steel production, railway building and dockside labour. In the next few decades, because the area was rich in coal, many of them settled in Kilsyth, Croy, Smithston, Auchinstarry, Drumglass, Craiglinn, Twechar, Condorrat and Cumbernauld.
 
In 1832 there were about five Catholic families in the Kilsyth area. Between 1849 and 1863 the number grew from one hundred to six hundred. In 1862 Rev John Gillon from Lennoxtown began a new church mission in Arnot's Hall, Charles Street, Kilsyth to satisfy the needs of the fast growing Catholic population. By 1866, there were eighteen hundred Catholic families in the area due to the availability of employment and housing in Kilsyth and to the south of the Kelvin. The development of the Catholic community in Kilsyth and its environs was augmented by the arrival of Kilsyth's first priest, Father John Galvin on 5th January 1865. Worthy miners and their families trekked from the outlying villages to attend the 11.30am mass in Charles Street and from St Patrick's Day on 17th March 1866, in the brand new St Patrick's Church in Low Craigends.