It is currently residing in the Bendigo Art Gallery ahead of the Tudors to Windsors: British Royal Portraits exhibition that will open in March.

The full-length portrait shows the long-serving King of Britain in his coronation robes and is one of numerous replicas issued by the studio of Allan Ramsay.  The original remains in the Royal Collection.

Bendigo Art Gallery curatorial manager Tansy Curtin said the restoration took six months to complete.

“There's a few reasons (the restoration was required),” she said. “The work had been on display at the law courts for a number of years in a less than ideal conservation situation but also the paint never adhered to the canvas properly, so there was flaking paint and the surface was damaged.

“What we've done is preserved it for hundreds of years to come. You can see the difference. It really comes to life with this restoration.”

The full-length portrait has had its old canvas removed and relined as well as a complete restoration of the surface.

Ms Curtin said the painting is one of 18 full-length coronation portraits of King George III commissioned from the Allan Ramsay studio in the 18^th century.

“We knew works like this were commissioned by members of royal family or members of the aristocracy,” Ms Curtin said. 

“When we took the lining canvas off, we found writing on the back that designated it was to be returned to the Earl of Sandwich in Huntingdon. I had a hunch it came from that collection but this was clear evidence. 

“How it got to Bendigo, we’re not quite sure. It was sold from the estate in the 1960s and between that time and 1985, when it was given to Bendigo Art Gallery, it must have been purchased a private individual then given to us.

“It’s quite a incredible story of it going from a land of gentry in the UK to Bendigo in provincial Australia.”

Tudors to Windsors: British Royal Portraits will open at Bendigo Art Gallery on March 16 and run to July 14.

It features more than 150 treasures from London’s revered National Portrait Gallery, many of which have never before been seen outside the United Kingdom. 

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