A season for crying in the chapel: Millions will enjoy today's festival of carols from King's College, Cambridge. But Graham Chainey mourns a botched 'restoration'

December light is dying in the Tudor glass. Vaulting high over the candles and the surpliced choir is the noblest stone ceiling in existence. It is Christmas Eve, and a packed congregation of 1,800 and a worldwide radio and television audience of millions are listening as a boy's voice intones the first lines of 'Once in Royal David's City'. The Festival of Nine Lessons and Carols from King's College, Cambridge has become as much a part of Christmas as the turkey and the Queen's broadcast.

Since 1918, when the chapel held its first such service (it was first broadcast in 1928), King's College has become the guardian of one of Britain's most cherished traditions. And since 1446, when with his own hands the college's founder, Henry VI, laid the chapel's foundation stone beneath the spot intended for its high altar (the stonework was not to be completed until 1515, the glazing to continue until 1547), King's has been the guardian of one of Britain's most magnificent architectural monuments.

In recent decades, however, its exercise of that privilege has been controversial, to put it mildly - with parts of the chapel ruined in the eyes of many people by inappropriate and even crude additions and alterations.

The most notable example was the alteration made to the chapel in the Sixties to incorporate a grossly incompatible Rubens altarpiece, The Adoration of the Magi. This massive painting measures 11ft by 8ft and weighs 15 cwt (it is painted on wood), and was dashed off by Rubens in eight days in 1634 for a convent in Louvain, Belgium. Not everyone admired it. Sir Joshua Reynolds, who saw it at Louvain, thought it 'a slight performance', while Emperor Joseph II rejected it for his collection. It came to England and was acquired by the Duke of Westminster, who 'never thought highly of it'. It is a bravura, brilliant, superficial work. The eye is on the kings rather than the Christ child.

The Rubens was sent to Sotheby's in 1959 to pay death duties, and was knocked down to an anonymous buyer for the world record price of pounds 275,000 - Paul Getty was an unsuccessful bidder. The new owner turned out to be a property millionaire, Major A E Allnatt, who intended to give the picture to the National Gallery. But when the gallery's trustees allegedly failed to keep appointments with him, he decided to donate it instead to some appro=priate large church.

Allnatt, a keen racegoer, liked to stop off to attend evensong at King's on his way home from Newmarket, and had long wanted to benefit the chapel. So when a fellow of King's who happened to be a Rubens expert, Dr Michael Jaffe, suggested that the (as yet anonymous) buyer might consider King's as a recipient, this must have coincided with Allnatt's own thoughts. In March 1961 he inquired whether the college would like the picture.

Jaffe had spotted a major opportunity, for the college was already planning alterations to the chapel's east end. It was felt that the existing arrangement, with a columnated classical reredos installed in 1911, did not provide an adequate climax to the building. At evensong in winter, the altar tended to disappear into dark-panelled gloom.

When the governing body of King's met in May 1961, it unanimously accepted 'this munificent gift and rare addition to the worship, dignity, and beauty of the Chapel' and undertook to place it 'either in the antechapel above the archway of the organ screen or as an altarpiece whether in the choir or in the antechapel'. A letter from Sir Kenneth Clark was read urging the college not to be influenced by any argument that a baroque picture would be out of place in a Perpendicular Gothic church. Among other art experts consulted, only Sir Nikolaus Pevsner opposed the idea.

No suggestion, in the debates that followed, was to be as bizarre as that original one to hang the Rubens on the organ screen. Dating from the 1530s, the exquisitely carved screen is one of the glories of King's ('the finest piece of woodwork this side the Alps' said one admirer), while the 17th-century organ front perches beautifully above it. Placed there, the Rubens would have ruined the appearance of both.

The altarpiece arrived at King's on 15 November 1961 (it took 10 men two hours to get it across the college court) and was installed provisionally on a special easel in the antechapel near the south end of the organ screen. Here it remained for two years, some people favouring its permanent retention in this position. However, it did obscure the screen.

Once Allnatt's gift was in the building, the problems of assimilating it became apparent and the unanimity shown hitherto by the college fellowschanged to bitter disagreement. However those who wanted the Rubens as altarpiece at the east end - they included Jaffe, Provost Noel Annan, Vice-Provost L P Wilkinson and the bursar, A N L Munby (who struck up a friendship with Allnatt and used to go on treasure-trails with him) - had made up their minds, and were to prove insuperable.

Indeed, before the picture had even arrived they ordered that the existing altar and altar steps be dismantled. The responsible college committee was virtually run by Jaffe and at least one member resigned from it in protest at his manner. Shortly after the picture's arrival, the church architects Maguire and Murray, unwilling to incorporate it into their designs for the east end, were sacked and replaced by a more co-operative architect, Sir Martyn Beckett.

The arguments against the installation of the Rubens as altarpiece at King's now seem compelling. One reason was that a baroque 17th-century picture would clash tonally with the peerless Tudor stained glass in the east window above it. Another was that the Edwardian reredos, which many people liked, would be incompatible with it. A third was that it was simply too big: in order to get it beneath the east window without obstructing the glass, the floor would have to be levelled and the existing sequence of ritual steps - required by the founder in his will of 1448 - would have to go. The altarpiece faction set out to overcome these difficulties.

Early in 1964 the Edwardian reredos and the fine 17th-century panelling linking it to the choir stalls were stripped out, leaving the walls bare. In April the Rubens was transferred to the east end, reframed (the old frame was sold to Michael Heseltine) and placed experimentally beneath the east window at the height it would be if the floor were levelled.

Jaffe dismissed the removed woodwork as 'brown Windsor soup' and called the Rubens 'the obvious and magnificent focus for the east end'. Walking backwards and forwards, he and Beckett 'demonstrated that the painting does not cut into the bottom of the east window until one is really too close to the painting to appreciate it'.

To the criticism that the Rubens conflicted with the window, Beckett guardedly replied: 'Once you are through the organ screen you are either looking at the picture or you are looking at the window.' The problem that the Rubens, being roughly the same shape as the window but much smaller, would seem dwarfed and trivialised, was eventually solved by the addition of shutters to either side of the painting, giving a sham triptych effect.

After years of wrangling, Beckett's design for the east end - the Rubens as altarpiece, naked walls with curious modernistic light-sconces fixed to them, a jazzy new altar frontal and a levelled and redesigned floor - went before the college's governing body on 30 November 1965.

Twenty-one fellows and one honorary fellow (E M Forster) had signed a paper condemning the proposals on grounds which included the tonal clash, a feeling that the altar was 'becoming virtually an appendage to a picture', the stripped walls, the 'various metal objects' attached to the walls, the bogus triptych effect, and the belief that the Rubens had looked better in the antechapel. Fearing that 'enthusiasm for a great work of art, the Rubens, may lead to the spoiling of an even greater one, the Chapel', they called on the college to 'admit that it has made a mistake'.

Letters from experts read out at the meeting were, however, in favour (one from Sir Kenneth Clark expressing a change of opinion since 1961 was allegedly suppressed) and the scheme was approved by three votes. It was to be implemented during a 'restoration' of the chapel's interior during 1968.

Anxiety spread, however, about what was being done to one of the nation's most celebrated buildings, and in October 1966 the Royal Fine Art Commission descended on King's. Its involvement was ambiguous - Annan initially told the commission that the college was 'entitled to do as they like' with the chapel - and came too late. Its verdict was that had it been asked its opinion at the outset 'it is doubtful whether any members would have advised in favour of an attempt to use the picture as an altarpiece' - Henry Moore and John Piper were particularly vehement. In the circumstances the commission could only suggest minor alterations, which the college ignored.

Curiously, neither the 21 dissident fellows nor the commission questioned the levelling of the floor. Beckett and Jaffe repeatedly described this as a 'restoration of the original level,' maintaining that the sanctuary floor had always been level prior to alterations in 1774 by the Gothic revivalist James Essex.

In fact, the founder had left precise instructions that the high altar should be raised 3 ft above the choir floor. A step known as the gradus chori, immediately east of the choir stalls, had been there since the earliest times, and there had always been further ritual steps.

Nor did anyone mention that until 1774 the sanctuary had been used for burials. On a plan of 1609 the chapel's two eastern bays are clearly marked: 'The place where they bury in', while in 1742 it was recorded that the east end was 'peculiarly appropriated for the interment of the senior fellows'.

When the sanctuary floor was taken up in 1968, it was found to rest on Tudor brick arches - proving that the raised levels were not an 18th-century addition. These arches were destroyed. (The bricks were allegedly 'carted off piecemeal by various fellows to make patios and the like').

As the workmen dug beneath the arches, scores of human remains were apparently exhumed - skulls, skeletons and intact lead coffins with engraved brass plates, dating from the 15th to the 18th centuries. According to a witness, the workmen refused to continue until the remains had been decently removed. The dean, David Edwards, was called in to conduct a brief ceremony.

No record seems to have been kept by the college (despite its reputation for historical scholarship) of how many remains were found, or in what locations, or of the identity of those that could be identified, nor of what was done with them. No permission was obtained from the bishop for their disinterment. Despite the obvious interest of the find, no mention of it appeared in print. Neither the chaplain nor the lay dean were informed. Edwards (now Provost of Southwark) and Jaffe (former director of the Fitzwilliam Museum) have maintained silence on the subject; Beckett will say only that 'one, perhaps two' coffins were unearthed. No effort was apparently made to locate Henry VI's foundation stone.

As soon as the brickwork and bones had been cleared away, the sanctuary was concreted over and the marble relaid. In disturbing the remains of their predecessors, the fellows of 1968 appear to have achieved what the notorious Puritan iconoclast William Dowsing failed to do at King's in 1643 when, sent to 'reform' the Cambridge churches, he 'digged up the floors of our chapels, many of which had lain so for two or three hundred years together, not regarding the dust of our founders and predecessors, who likely were buried there'.

The 'restoration' work completed, King's College Chapel reopened at Christmas 1968 to a storm of controversy. Hugh Montefiore, then vicar of the University Church, Great St Mary's, protested that there was no longer a cross on the altar, apparently to improve the view of the Rubens. Others castigated the bare walls, the altar frontal (it was removed in 1989), the conflict between the Rubens and the east window, or the gimcrack light fittings. The Architects Journal summed up the ensemble as 'motivated not by the demands of liturgical worship but by those of museum display'.

The criticism has never abated. Pevsner wrote in 1970 that 'if any building in the whole country was not made for (the Rubens) it was King's College Chapel', while the architectural historian Gerald Cobb felt the choir had been 'devastated' by the removal of the panelling. Gavin Stamp called the alterations 'donnish barbarities' and 'the most reprehensible of all examples of contemporary arrogance' in architectural restoration. John Julius Norwich in 1985 felt that the Rubens destroyed the chapel's inner harmony 'as cruelly as an F sharp in the middle of a C major chord'.

The publicity surrounding the affair culminated, in 1974, in the picture being vandalised, when the letters 'IRA' were scratched across it. Since then the chapel's eastern bay has been isolated with security barriers, so that the Rubens has to be viewed from a distance of 25 ft, which, together with closed-circuit cameras and vandal alarms, further diminishes the devotional atmosphere.

The spirit of 1968 was continued in 1986-87, when further 'donnish barbarities' were inflicted on the building. Even though the public had been asked only a few years before to contribute pounds 1m for essential repairs to the exterior, the college decided to allocate a figure rumoured to be well into six figures to set up, in seven of the northern side-chapels, a tourist exhibition of notable vulgarity.

Objects of genuine historical interest that were already in these side-chapels were evicted or concealed to make way for facsimiles and mock-ups which reduce the building's inspiration to the level of the cutaway model and the school project. The entrance to this exhibition, in which a 15th-century vault with carved bosses has been hidden behind a pseudo- royal tent, sets the general tone. A 15th-century monumental brass that was in the way of the entry ramp has been nailed to the wall behind part of the display.

The college's attempts to turn the great sacred building into a staging post for tourists on the road from Madame Tussaud's to Stratford-upon-Avon is evident in the recently revamped and expanded gift shop filling a corner of the antechapel. Perhaps uniquely for a church shop, it has no Christian literature on sale.

One of the most interesting side-chapels, the Hacumblen chantry, with its early stained glass and its monuments, has been turned into a marmalade store. Another, formerly furnished as a chapel for the commemoration of founders, is now a chair store. The Deposition by the 16th-century artist Siciolante da Sermoneta that served as the chapel's altarpiece before the donation of the Rubens is also inaccessibly stored here.

For many people, this may not matter. King's is only an annual radio service or a recorded television spectacular, or else a 10-minute stroll down a crowded aisle loud with tour guides. But for those for whom this chapel is special, a building without peer, uniquely magnificent for its architecture, its stained glass, its woodwork and its music, it matters a lot. In 1968 one of the most inspiring interiors of any Christian building was spoilt to make it accommodate a picture that did not belong there; and the insensitivity of those who own the building towards its powerful spiritual quality shows no sign of diminishing.

Graham Chainey edited 'In Celebration of King's College Chapel', Pevensey Press, 1987.

(Photograph omitted)