THERE are very few dates on which you can say that the history of Scotland changed utterly. September 11, 1297, and June 23-24, 1314, obviously, while the birthdates and dates of death of monarchs certainly qualify, as does May 1, 1707 and July 1, 1999, and if you need to check what happened on those dates then you haven’t been paying attention.

On the list of most important dates should be May 18, 1843, though I suspect not one in 20 readers – except those who got the hint in this column in The National last Tuesday – will know immediately what happened in Edinburgh on that day.

The Disruption was the single most dramatic and momentous event in the history of the Church of Scotland since the Reformation itself.

From the outset, let me state that I have no side in this examination of the Disruption. I will merely record the facts and readers can, if they so choose, decide who was in the right and who was in the wrong.

To recap, for more than 150 years the Church of Scotland, the state-recognised national religion of this country, had been suffering from civil war over the issue of patronage – the power of local lairds, councillors and landowners to appoint ministers to their local kirks over the heads of their congregations.

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That right had been removed in 1690 by an act of the Scottish Parliament only to be restored by the Patronage Act passed in Westminster four years after the Union. It was hugely unpopular but was not only occasionally challenged until about a century later when there emerged a group of so-called “Evangelicals” within the Kirk.

They wanted stricter adherence to the Bible and a break with the state, but they were opposed by the “Moderates” who were the majority in the Kirk and who backed patronage and did not want an argument with the State.

At the start of the 19th century the Evangelicals began to win the day so that in 1834 the General Assembly passed the Veto Act, starting what became known as the “10 Years Conflict”. This Kirk Veto Act allowed a majority within a parish to reject a patron’s choice of minister, though only men who were heads of families could vote.

As we saw last week, the Evangelicals reckoned without the State and its right-hand men, the judges in the Court of Session whose principal ruling was that the General Assembly had acted “ultra vires”, beyond its powers, in passing the Veto Act. It was nothing less than a declaration of war against the proud religious independence of the Kirk.

It has to be recognised that what happened on May 18, 1843, was no explosion of temper, no crisis hewed in a few seconds. On the contrary the Evangelicals had been planning for the Disruption for months, maybe even years.

In 1842, the General Assembly drew up a Claim of Right. It stated that Jesus Christ was head of the church, not the government in Westminster.

The Evangelicals and Moderates both began to mobilise their forces, with the former stating it was willing to cause a schism and walk out of the Kirk – what leading Evangelical the Rev. Thomas Chalmers named the Disruption.

In November of 1842, the Evangelicals held a Convocation and duly presented to Parliament in London a “Claim, Declaration and Protest anent the Encroachments of the Court of Session”.

Chalmers made their position clear. His 400-plus colleagues and he – around one-third of the ministry – were willing to walk away from their jobs, their incomes and their homes in pursuit of a Kirk that was free of patronage and state interference.

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“Not that we renounce the principle of a National Establishment of Christianity,” he wrote, “for we think it quite possible to harmonize this with the principle of spiritual independence.

“It will be the fault of our rulers if the two are not harmonized; and I do hope that we shall get a little more credit at the hands of our adversaries when they find us giving up all the endowments of a National Church so soon as it is determined that we shall not be permitted to hold them but at the expense of our Christian liberties.”

The Evangelicals were also confident of something else – they knew they had the support of almost half of the lay people in the Kirk, so successfully had they made their case.

The answer from Parliament came in January, 1843, and was blunt – the status quo would be preserved and the Court of Session would continue to have civil law supremacy over the Kirk. The Evangelicals were now convinced that Disruption was the only answer.

The General Assembly of the Church of Scotland was set for St Andrew’s Church in George Street, Edinburgh, on May 18.

Plans were made in advance for the events of that day which shocked Scotland – perhaps two-thirds or more of the population were adherents of the national Kirk and church affairs were the stuff of conversation across the land.

The Evangelicals knew they did not have the numbers to force the Kirk to adopt their position of opposition to the State, but they also knew that they had quite sufficient support to do the one thing that the Moderates feared – split away and start what would in effect be a new Presbyterian church. They were also aware that with the likes of Thomas Chalmers, the brilliant preacher the Rev Robert Smith Candlish and the Rev David Welsh, their side had most of the finer intellects in the Kirk at that time.

Welsh was in fact the retiring moderator of the General Assembly that year so that meant that it would be he who would open the meeting and be the first to speak.

People queued from the early hours of that Thursday morning and every seat in the venue was taken, with many hundreds more standing outside, the general public of Edinburgh well aware that they were witnessing history.

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The morning saw the pageantry of the Lord High Commissioner, Queen Victoria’s representative, the Marquess of Bute hosting a reception at Holyrood Palace where a curious incident took place – a portrait of William III fell from the wall. He was of course the king who had negotiated the Settlement of 1690 that had caused the Patronage row in the first place …

The usual procession made its way to the Assembly Hall on George Street where the Assembly had been waiting for hours. After acknowledging the High Commissioner, the Assembly offered up solemn prayers.

Welsh got to his feet and the crowd strained to hear him. Like a thunderclap his words soared out: “I must protest against our proceeding further.”

As his listeners became solemn and sombre, Welsh continued to read the Protest he had prepared earlier.

“We protest, that in the circumstances in which we are placed, it is and shall be lawful for us, and such other Commissioners chosen to the Assembly appointed to been this day holden as may concur with us, to withdraw to a separate place of meeting, for the purpose of taking steps, with all who adhere to us, maintaining with us the Confession of Faith and Standards of the Church of Scotland, for separating in an orderly way from the Establishment, and thereupon adopting such measures as may be competent to us, in humble dependence on God’s grace, and the aid of the Holy Spirit for the advancement of His glory, the extension, of the Gospel of our Lord and Saviour, and the administration of the affairs of Christ’s house, according to His holy Word: and we now withdraw accordingly, humbly and solemnly acknowledging the hand of the Lord in the things which have come upon us, because of our manifold sins, and the sins of the Church and nation; but, at the same time, with assured conviction that we are not responsible for any consequences that may follow from this our enforced separation from an Establishment which we loved and prized, through interference with conscience, the dishonour done to Christ’s crown, and the rejection of His sole and supreme authority as King in His Church.”

Welsh laid his Protest on the table, bowed to the Marquess of Bute and walked out. Thomas Chalmers had stood as if awestruck at the magnitude of what they were doing, but quickly roused himself and led the mass walkout.

A few cheers rang out from the viewing gallery, but people soon quietened when more and more ministers and elders made their way solemnly out of the Assembly venue. Think Ian Blackford and the famous SNP walkout in the House of Commons and you don’t even get close to the sensation which Chalmers and his colleagues caused.

In all, 121 ministers and 73 elders walked out. In George Street they were joined by many more ministers and elders and were cheered to the echo by the public.

They all walked downhill to Tanfield Hall in Canonmills, where Thomas Chalmers was duly elected Moderator of the new kirk whose name was already decided – the Free Church of Scotland.

We know what they looked like that day. The painter and photographer David Octavius Hill attended, and later produced the amazing photo of that Disruption Assembly – he photographed each person separately and “photoshopped” them together.

A total of 474 ministers quit the Church of Scotland that month and many more elders joined them, about a third of the Kirk’s leadership in all. As Chalmers had hoped, lay people flocked to them. The 1951 census recorded just 32% of Scots adhering to the Church of Scotland, half the membership figure at the time of the Disruption. Scotland did not then have one national kirk, but two.

Something utterly extraordinary then happened. All of these ministers had been flung out of their manses and kirks, and the “school in every parish” so necessary for Presbyterians now all belonged to the Church of Scotland.

In the midst of an ongoing recession, Chalmers led the way in establishing the Sustenation Fund into which every member of the new Free Kirk pledged a penny a week.

Over the next five years, the new Free Church built over 750 churches, 500 primary schools – the so-called Ragged Schools – and several theological colleges, Chalmers becoming first principal of New College.

One of the greatest achievements was to construct an active overseas mission, with Free Church ministers behind settlements in Australia, Canada and New Zealand.

Their success also changed the Church of Scotland which began to take a more liberal view of society as well as finally accepting that patronage was dead.

The Kirk’s own website history tells how it all ended: “In 1874 Parliament finally abolished patronage and this opened up the prospect of re-union, though that would take time and, again, be achieved in stages. In 1900 the Free Church and the United Presbyterian Churches came together to constitute the United Free Church which united with the Church of Scotland in 1929.”

The radicalism of the Evangelicals also stirred something in the spirits of the people of Scotland. They led the way in religion, but many others followed their example and chose the radical way in all sectors of society.

Political engagement by working people and trade unionism developed rapidly in the rest of the century. We are their heirs yet.