A unique piece of Scotland's religious history has been preserved thanks to a £2m restoration project.

The 16th century heraldic ceiling of St Machar's Cathedral, Aberdeen, comprises 48 coats of arms including that of Pope Leo X, King James V of Scotland, Henry VIII of England and many of the royal houses of Europe.

An exquisite piece of medieval carpentry that attracts visitors from around the world, it was commissioned in 1520 by Bishop Gavin Dunbar and survived the turbulent years of the Reformation.

It was due to mark its 500th anniversary in 2020 when worrying signs of deterioration were detected, including a mysterious white substance on the shields that turned out to be stearic acid produced by the breakdown of linseed oil used to treat the ceiling.

"Without investment now, it would have led to a situation where it would have been very hard to maintain," said St Machar's minister Rev Sarah Brown.

To show off the newly restored ceiling in all its glory, new lighting has been installed by Malcolm Innes Design.

St Machar's is the oldest building in Aberdeen still in use and its ceiling is an important part of its legacy for Rev Brown. 

"It represents how central the church was in both Scottish and European history and I suppose that legacy still lives on with the number of visitors who come from all over the world to see the church and particularly the ceiling," she said.

"For me, that's what it signifies, that sense of people 500 years ago investing in a faithfulness that is still being lived out."

Professor David Hewitt, who was closely involved in the restoration, explained the significance of the ceiling: "Having a heraldic ceiling is extraordinary for a church. There are others over the course of the 16th century, but St Machar's is the first and it is really one with a political message for Scotland and Western Europe.

"Here are 48 shields representing Europe, of which the Pope is at the centre, the kings of Europe down the north side and the King and regents of Scotland down the south side.

"It's talking about a united Christendom under the Pope with ecclesiastical power supported on either side by secular power and all under God. It really ought to be better known."

Two years later than planned owing to Covid and the extensive restoration work, the ceiling's 500th anniversary is being belatedly celebrated this weekend with a programme of events include a thanksgiving service led by the Moderator of the General Assembly of the Church of Scotland, Rt Rev Dr Iain Greenshields.

The ecumenical thanksgiving service will be attended by 250 guests including Church of Scotland, Catholic and Scottish Episcopal clergy, former Moderator and Pro-Chancellor of the University of Aberdeen Sir Iain Torrance, and representatives from the consulates of some of the countries represented on the heraldic ceiling. 

Rev Brown hopes the celebrations will inspire many more people to come and visit the cathedral.

"Having this opportunity to open the doors is something quite special especially after having been forced to close during Covid and I hope this weekend lets people know that the cathedral is open year round and that this is a space they can enjoy," she said.

"It's also a great opportunity to invite some of our neighbours and some of the groups and community projects and just offer them the chance to see what St Machar's looks like in all its glory."