The First World War saw a collapse of the old order across Europe, and in Wales organised Christianity went into a long decline.
Lloyd George's promise after World War I to create a land fit for heroes rang hollow in many people's lives. The carnage of the war led to a questioning of the old certainties, and developments in politics, education and the media reflected this change. The word of God was no longer unchallenged at a popular level. Darwin's explosive theory regarding the origins of mankind had been around for fifty years, and the Bible's account of creation was now a matter of everyday debate.
Young socialists like Aneurin Bevan in Tredegar rejected the beliefs of their Nonconformist parents in favour of the promise of Socialism.
The chill winds of the depression from the mid 1920s onwards saw a fight back from Christians who wanted to act on their principles and actively do something to improve the living conditions of people, particularly in the poverty-stricken valleys of south east Wales. Christian Socialism's founding father was the 19th century philanthropist Robert Owen, from Newtown in Powys.
Robert Owen's principles inspired a new wave of Christian activity in the valleys. In Tonypandy the Wesleyan minister Rex Barker opened a famous social centre in the town's Central Hall. In 1936 he wrote an influential book based on his experiences, 'Christ In The Valley of Unemployment'. Also in the Rhondda the Quakers established another social centre at Trealaw, called Maes-yr-Haf.
These good works among others are testament to the good intentions and deeds of committed Christians, but their efforts were dwarfed by the sheer scale of the suffering at that time.
The Second World War finally kick-started the Welsh economy by increasing the demand for coal and the building of munitions factories to serve the war effort, but both the war and the immediate post war world proved to be another kick in the teeth for religion. Newsreels showed cinema audiences the horrors of the war, and although Christians responded by arguing that war was an act of man, popular sympathy was not on their side.
Peacetime brought further benefits of the material world. The coming of the car increased mobility. No longer were people confined to their communities on the Sabbath, with no choice apart from going to chapel three times. Now they could drive to the seaside, or visit whoever they wanted. They weren't limited, whereas chapel life seemed to be restricting.
Dylan Thomas' 'bible-black' phrase from 'Under Milk Wood' neatly captures the dour image of religion, as does the famous quote of the Rhondda writer Gwyn Thomas - "There are still parts of Wales where the only concession to gaiety is a striped shroud."
The existence of the Sunday Closing act in parts of Wales down to the 1990s also continued the impression of a culture that liked to say no more often than it said yes to the simple pleasures of life. The arrival of the 'permissive society' in Wales sometime in the 1970s was to be bad news for this particular way of life. These new freethinkers had little time for the severity of the chapels, and this happened at a time when the last great generation of chapel goers was starting to die off.
As they were not being replaced by new recruits, chapels began to close down. Some were converted to new uses such as homes, shops, even an adult film cinema. Others were simply left to rot.
The 2001 Census shows that today in Wales fewer than one in ten people regularly attend a church or chapel, slightly lower than the figures for Scotland and England. However, it also shows that over 70% of Welsh people see themselves as Christian, perhaps demonstrating that while they don't actively worship God, their lives are still strongly influenced by Christian values and principles. And that is not really surprising in historic terms, because one of the defining characteristics of the Welsh is the Christian religion.
This particular legacy of the Roman Empire, combined with the language, differentiated the Welsh from the invading Germanic pagan tribes of over 1,500 years ago. Therefore, if Christianity does die out in Wales, the question arises as to what kind of country Wales will be.
It cannot be denied that Christianity has made an important contribution to the development of Wales since its arrival in Britain almost two thousand years ago. And if it is correct to say that the future of Christianity in Wales is unknowable, then it is equally correct to say that the history of Wales is unknowable without a proper acknowledgement and respect of its Christian origins.