To mark the fourth centenary of Mattia Preti’s birth, the St John’s Co-Cathedral Foundation has restored his painting The Allegory of the Triumph of the Order of St John above the main doorway of the cathedral.

The inauguration ceremony will be held on February 22.

The Allegory forms part of the impressive cycle that narrates the life of St John the Baptist painted between 1661 and 1666 during the magistracy of the two brothers Raphael and Nicholas Cotoner, who were Grand Masters of the Order from 1660 to 1663 and from 1663 to 1680 respectively.

Preti was born on February 24, 1613, in Taverna, a small town with no progressive school for artists; he soon moved to Rome, and later to Naples. The artistic influences of both cities set his formation and account for his scenographic skills reminiscent of Pietro da Cortona and his life-long affinity with Caravaggism.

Preti’s first encounter with the Order was in October 1642 when he was invested as a Knight of Obedience, which is why he was known as il Cavaliere Calabrese. His association with the Order would shape the course of his career.

One of the most exuberant scenographic works of the high baroque style in the 17th century, The Allegory of the Triumph of the Order is instantly recognisable as one of the most iconic images of the Knights of St John- Cynthia de Giorgio

Preti’s next contact with the Order was in March 1658 when he was commissioned by Grand Master Martin de Redin to produce a painting of St Francis Xavier. Saints have always had a special place at the centre of Christian devotion since the early days of the Church. The increased popularity in depicting scenes from the life of saints was essentially in response to challenges made by the Reformation to fundamental doctrines of the Catholic Church.

Attracted by patronage, Preti visited Malta in 1659 and donated a painting representing St Catherine to the Italian langue. Then in September 1661 Grand Master Raphael Cotoner informed the council of Preti’s offer to paint “the vault of our major church”. As a result, Preti was elevated to Knight of Grace.

In the glorious scenes from the life of St John the Baptist, Preti created an intensely imagined and heavenly world. Initially, the first Counter-Reformation art was harsh but by the early 17th century the down-to-earth realism that had set the tone of the Catholic Reformation of the early 1600s began to relax.

Preti responded to this positive change in climate and translated it into some of the most glorious and triumphant religious imagery. The story is told according to the biblical sequence and starts from the first bay at the entrance with the vision of St Zachary in the temple and finally John beheaded at the hands of Herod. Preti’s Venetian treatment of the cycle, such as the atmospheric effects, the bright palette and painterly qualities reminiscent of Titian and especially Veronese, are testimony of a visit to Venice recorded in his epitaph.

For the vast lunette-shaped wall above the main door, Preti painted the Allegory of the Triumph of the Order. He created an interesting composition to symbolise the mission of the Order as hospitallers and defenders of the Catholic faith; painted with vigorous brushstrokes, this abstract subject is depicted in clear visual terms to document the victory of the Order of St John over the Turkish infidels.

He chose the allegorical figure of Victory to represent the Order, dressed in armour and helmet, brandishing a sword in one hand and holding the flag of the Order in the other, heroically trampling over Moorish figures. In the background lie slain knights and a fortified city in a scene that recalls the Great Siege of 1565. Angels and putti holding palm fronds, the symbol of martyrdom, descend from the skies to offer the palms to the deceased knights.

On either side of the doorway Preti depicted the two Cotoner Grand Masters; Nicholas tends to the sick while Raphael points towards a picture of the galleys of the Order. Nicholas, who had just been elected Grand Master in 1663, is accompanied by two youthful pages to hold his hat until his duties have been completed.

This was the last phase in the decorative scheme of the vault, after alterations were made to the doorway in 1665, and on December 20, 1666, the painting of the vault was declared “completed to (our) full satisfaction” by Grand Master Cotoner and his council.

Preti executed the entire vault painting by using an oil-on-stone technique rather than the usual fresco method for wall paintings. He knew that the Maltese globigerina limestone when soaked in linseed oil could easily be painted with oil-based pigments. This procedure served him well and he used the golden hue of the oil-soaked stone as a background, saving him several hours of having to fill in vast areas with colour.

The history of the restoration of the vault and lunette dates back to 1868 when the artist Carlo Ignazio Cortis was employed to carry out the restoration. The paintings had suffered extensive deterioration caused by rainwater filtering through the roof. His intervention consisted mainly of extensive over-painting, a method he employed to cover the losses that in the absence of an established restoration methodology gave way to artistic licence.

It was immediately recognised as a disaster, and in 1920, Vincenzo Bonello, Inspector of Works of Art, wrote about his concerns. Preliminary investigations were carried out by Bonello who subsequently, between 1932 and 1936, directed the cleaning of the entire vault that had been covered by a layer of salt efflorescence.

Eventually a protective roof was installed over the nave, as mentioned in Cesare Brandi’s report of 1952. The Istituto Centrale per il Restauro, Rome, was then engaged, and between 1932 and 1936 under Brandi’s direction carried out the restoration of the vault, which consisted of removing the salts and the previous intervention by Cortis. Brandi’s work showed that the vault paintings had suffered extensive deterioration and in some areas figures are faint and the opulent colours are severely faded.

The current restoration of the lunette, which started in August 2011, uncovered Preti’s original work preserved almost intact. The supporting wall did not suffer the deterioration caused by water infiltration as the vault had experienced. The painting was suffering only aesthetically, from the accumulation of dust deposits on the stone courses and discoloured varnishes caused by the baking sun on the exterior southwest-facing wall.

Studies showed that the stone support and the paint layer were in a surprisingly sound state of conservation, which is testimony to the compatibility of materials originally used and the manner in which they were first employed in the execution of the painting. The wall painting had some loose mortar joints and previous reconstruction in several of these areas showed that this was not the first time they occurred. Scientific tests were carried out to analyse the composition of the pigments and materials used by the artist and the additional materials employed by subsequent restorers.

The first stage in the restoration intervention was the removal of the thick layer of dust that had settled on the irregular stone surface. After this process it was possible to study the surface, which confirmed that the materials from past restoration attempts, such as protective layers of varnish and heavy glazes of colour, had altered with the passage of time, causing visible changes in the overall aesthetic appearance of the painting.

The oxidised varnish and residues of the over-paintings applied previously were especially noticeable in portions of the sky. In order to find a method that would remove oxidised varnish and over-paintings, several cleaning tests were carried out with various solvents to reach a method and technique that would yield the best results without causing any damage to the original paint layer.

The current restoration of the lunette uncovered Preti’s original work preserved almost intact- Cynthia de Giorgio

Once the cleaning methodology was established, the process was applied throughout the lunette and first register. The selected cleaning method consisted of a mixture of organic solvents followed by the application of ion exchange resins, which was carried out using brushes and cotton swabs. As a result, the cleaning process revealed the vibrant colours and the original brushstrokes of the artist.

Areas of loose plaster were consolidated with acrylic adhesive while deep cracks in the mortar joints were consolidated by injecting them with a hydraulic lime-based grout. During the treatment these areas were held in place with Japanese paper.

After cleaning and consolidation, the painting was retouched with watercolours using the rigatino method, which is a series of fine parallel lines for the restoration intervention to remain easily legible. This method was applied to conceal the visible mortar joints and give an overall aesthetically appealing result.

The final stage was the application of a diluted layer of varnish to revive the colours and act as a protective layer to the paint layers.

The cleaning provided the opportunity to view Preti’s original brushwork at close proximity. His vast colour scheme consisted of lucid pastel shades for the skies and thick vibrant colours for the figures and drapery. Facial contouring and expressions were built up with glazes and strong dabs of colour. He loosely sketched in the architecture framework with charcoal, leaving the golden hue of the oil-saturated stone as background and clouds, and applied large washes of pale blue for the skies.

The figures do not seem to be drawn in and are built up with broad and rapid brushstrokes laden with pigment. Dabs of paint were used for highlighting his figures, which are impressionistic in style and show Preti’s technical confidence and knowledge of painting large-scale compositions.

Preti introduced a grand manner, depicting his subject with unparallelled dramatic effect. The cycle displays his virtuosity and is one of the most exuberant scenographic works of the high baroque style executed in the 17th century. The Allegory of the Triumph of the Order is instantly recognisable as one of the most iconic images of the Knights of St John.

Preti ranks as one of the most outstanding baroque decorators of his time. Subsequently, on designs prepared by him, the walls of the nave and chapels were carved with elaborate motifs characteristic of baroque motifs ornamentation, transforming the walls into a riot of gilded foliage, angels and triumphal symbols. He also painted several of the altarpieces inside the chapels.

Preti’s artistic output was truly considerable and much of it was produced in Malta where he lived out the last 40 years of his life.

He died in 1699 and was laid to rest in the Conventual church of St John’s alongside other high-ranking knights, keeping a watchful eye on his greatest artistic accomplishment.

Acknowledgments go to Giuseppe Mantella Opere d’Arte, Francesca Muscat, conservator, St John’ Co-Cathedral Foundation, and Judge Giovanni Bonello.

The Foundation is organising two public lectures: the first will be held on February 28 by Prof. John Spike, an international authority on Mattia Preti, and the second on March 6 by Prof. Keith Sciberras, head of the History of Art Department at the University of Malta and an author of a book on the subject.

Ms Degiorgio is curator and CEO of the St John’s Co-Cathedral Foundation.