The Louvre is lending a Van Dyck portrait of Charles I. Photograph: Anthony van Dyck/Royal Academy of Arts/PA
Artworks acquired by Charles I which were sold off by Oliver Cromwell’s republican government are to return to the UK for a once-in-a-lifetime exhibition of one of the most stupendous art collections ever created.
The Charles I exhibition, a collaboration between the Royal Academy of Arts (RA) and the Royal Collection Trust, will reunite spectacular works by artists such as Titian, Van Dyck, Rubens, Holbein and Mantegna, some of which are coming to Britain for the first time in nearly 400 years.
It is the sort of exhibition art curators fantasise about, but was always seen as an “impossible dream”, according to Jonathan Marsden, director of the Royal Collection.
That is because so many of the finest works were sold abroad never to return, despite the efforts of Charles II to restore his father’s collection.
The exhibition will kick off the RA’s 250th anniversary year in January 2018. Christopher Le Brun, the president of the RA, said he had been hillwalking with Desmond Shawe-Taylor, the Queen’s surveyor of pictures, in 2012 and asked him if he could make the greatest exhibition of his lifetime what it would be: “In a flash, he said Charles I, the king’s pictures. Extraordinarily, we’ve done it.”
Charles I is the most important collector of art of any monarch in British history. He bought the best old paintings and commissioned the best contemporary artists, notably Anthony van Dyck.
But the civil war and the king’s execution in 1649 led to almost all the collection – an estimated 1,500 paintings and 500 sculptures – being sold by Cromwell and scattered throughout Europe.
The Restoration, under Charles II, saw a significant chunk of it reassembled, but many works were gone for good, including around 40 of the greatest works in the royal collections of France and Spain.
Those works now reside in the Louvre and the Prado and it was to these institutions that Shawe-Taylor and his co-curator from the RA, Per Rumberg, went with wishlists, aware they were asking for the stars.
The Louvre is lending three paintings, including two Titians (Supper at Emmausand Conjugal Allegory) which are often overlooked by visitors because they hang in the same room as the Mona Lisa.
It is also lending a painting Rumberg described as “arguably the most moving portrait Van Dyck painted of Charles I, and one of his greatest portraits”. He added: “It was not sold, it must have been a diplomatic gift to the French court … it has never returned since.”
The Prado meanwhile is lending five works including a Titian portrait of Charles V with his dog.
“Both galleries were extremely open and willing to collaborate,” said Rumberg. “It is extremely generous … Normally you are lucky if you get one or two. We count our blessings.”
There are five works coming from the National Gallery in London, including a major Van Dyck equestrian portrait, Charles I on Horseback. That will be hung alongside the other big equestrian portrait Charles I on Horseback with M de St Antoine, which hangs in Buckingham Palace – the first time anyone will see them hanging together.
The bulk of the loans, around 90 works, are being lent by the Royal Collection.
Other highlights include what Rumberg described as “arguably the most extraordinary set of tapestries ever made in England”. They too were given as a diplomatic gift to France and are to be found in the stores of the Mobilier National in Paris.
The four tapestries will be hung floor to ceiling on four walls facing each other in the RA’s lecture room.
As the RA concentrates on Charles I, the Royal Collection will, it said, present an exhibition on his son Charles II, which will include more than 220 paintings, miniatures, drawings, prints, books, pieces of furniture, sculptures, ceramics, tapestries and silver from the Royal Collection.
A third partner will be the BBC, which is planning a four-part BBC Four series, presented by Andrew Graham-Dixon, on the Royal Collection and a BBC Two documentary on the Charles I show, presented by Brenda Emmanus.