The Church of Scotland traces its roots back to the beginnings of Christianity in Scotland, but its identity is principally shaped by the Reformation of 1560. As of December 2013, its pledged membership is 398,389, or about 7.5% of the total population dropping to 380,164 by yearend 2014 according to official church statistics . According to a 2015 survey a significantly higher 25.3% of the Scottish population, or 1.4 million adherents, claimed some form of allegiance to it. In the 2011 census 32.4% claimed allegiance to the church. (see Religion in Scotland).
Presbyterian tradition, particularly that of the Church of Scotland, traces its early roots to the Church founded by Saint Columba, through the 6th century Hiberno-Scottish mission. Tracing their apostolic origin to Saint John, the Culdees practiced Christian monasticism, a key feature of Celtic Christianity in the region, with a presbyter exercising "authority within the institution, while the different monastic institutions were independent of one another." The Church in Scotland kept the Christian feast of Easter at a date different from the See of Rome and its monks used a unique style of tonsure. The Synod of Whitby in 664, however, ended these distinctives as it ruled "that Easter would be celebrated according to the Roman date, not the Celtic date." Although Roman influence came to dominate the Church in Scotland, certain Celtic influences remained in the Scottish Church, such as "the singing of metrical psalms, many of them set to old Celtic Christianity Scottish traditional and folk tunes", which later became a "distinctive part of Scottish Presbyterian worship".
While the Church of Scotland traces its roots back to the earliest Christians in Scotland, its identity was principally shaped by the Scottish Reformation of 1560. At that point, many in the then church in Scotland broke with Rome, in a process of Protestant reform led, among others, by John Knox. It reformed its doctrines and government, drawing on the principles of John Calvin which Knox had been exposed to while living in Geneva, Switzerland. In 1560, an assembly of some nobles, lairds and burgesses, as well as several churchmen, claiming in defiance of the Queen to be a Scottish Parliament, abolished papal jurisdiction and approved the Scots Confession, but did not accept many of the principles laid out in Knox's First Book of Discipline, which argued, among other things, that all of the assets of the old church should pass to the new. The 1560 Reformation Settlement was not ratified by the crown, as the monarch, Mary, Queen of Scots, a Catholic, refused to do so, and the question of church government also remained unresolved. In 1572 the acts of 1560 were finally approved by the young King James VI, the son of Queen Mary, but the Concordat of Leith also allowed the crown to appoint bishops with the church's approval. John Knox himself had no clear views on the office of bishop, preferring to see them renamed as 'superintendents'; but in response to the new Concordat a Presbyterian party emerged headed by Andrew Melville, the author of the Second Book of Discipline.
Melville and his supporters enjoyed some temporary successes—most notably in the Golden Act of 1592, which gave parliamentary approval to Presbyterian courts. James VI, who succeeded to the English throne in 1603 as James I, believed that Presbyterianism was incompatible with monarchy, declaring "No bishop, no king" and by skillful manipulation of both church and state, steadily reintroduced parliamentary and then diocesan episcopacy. By the time he died in 1625, the Church of Scotland had a full panel of bishops and archbishops. General Assemblies met only at times and places approved by the Crown.
Charles I inherited a settlement in Scotland based on a balanced compromise between Calvinist doctrine and episcopal practice. Lacking the political judgement of his father, he began to upset this by moving into more dangerous areas. Disapproving of the 'plainness' of the Scottish service he, together with his Archbishop of Canterbury, William Laud, sought to introduce the kind of liturgical practice in use in England. The centrepiece of this new strategy was the Prayer Book of 1637, a slightly modified version of the Anglican Book of Common Prayer. Although this was devised by a panel of Scottish bishops, Charles' insistence that it be drawn up in secret and adopted sight-unseen led to widespread discontent. When the Prayer Book was finally introduced at St Giles Cathedral in Edinburgh in mid-1637 it caused an outbreak of rioting, which, starting with Jenny Geddes, spread across Scotland. In early 1638 the National Covenant was signed by large numbers of Scots, protesting at the introduction of the Prayer Book and other liturgical innovations that had not first been tested and approved by free Parliaments and General Assemblies of the Church. In November 1638, the General Assembly in Glasgow, the first to meet for twenty years, not only declared the Prayer Book unlawful, but went on to abolish the office of bishop itself. The Church of Scotland was then established on a Presbyterian basis. Charles' attempt at resistance to these developments led to the outbreak of the Bishops' Wars. In the ensuing civil wars, the Scots Covenanters at one point made common cause with the English parliamentarians—resulting in the Westminster Confession of Faith being agreed by both. This document remains the subordinate standard of the Church of Scotland, but was replaced in England after the Restoration.