LONDON (REUTERS).- London's Dulwich Picture Gallery turns 200 in January, and the museum is in for a birthday treat of 12 masterpieces from around the world, one for every month of its anniversary year.

The paintings to be loaned to the gallery in the south of the capital including major works by Velazquez, Vermeer, El Greco, Veronese, Rembrandt, Ingres, Van Gogh, Gainsborough, Constable and Hockney.

"Dulwich is recognized internationally as a really important museum in the history of museums," said gallery director Ian Dejardin.

"So I felt able to go and visit and write to directors of major institutions that we've worked with over the years to suggest to them that they might like to lend what I suppose is a glorified birthday card.

"One loan, one masterpiece every month of the year. It's like an unfolding calendar, it's like a year long advent calendar of your dreams."

The rolling exhibit will be called "Masterpiece a Month" and the museums contributing works to the scheme include the Prado in Madrid, Florence's Uffizi, the Rijksmuseum in Amsterdam and Britain's Royal Collection.

Vincent Van Gogh's "Self-portrait," Diego Velazquez's "Don Sebastian de Morra" and David Hockney's "Mr. and Mrs. Clark and Percy" are among the paintings that will adorn the end wall of the gallery's enfilade space.

As well as the Masterpiece a Month exhibit, the oldest public art gallery in London is also staging a show dedicated to U.S. illustrator Norman Rockwell, most famous for his covers of the popular American magazine "The Saturday Evening Post" between 1916 and 1963.

The main summer exhibition will involve two artists - French born Nicolas Poussin (1594-1665) and 82-year-old American Cy Twombly.

Although born more than three centuries apart, the pair are connected by their emigration to Rome and interest in mythology and classical subjects. Twombly once said that if he could be born again it would be as Poussin.

In October, 2011 the gallery is exhibiting the works of artists Tom Thomson and the Group of Seven, 20th century Canadian landscape painters who "set out to find the language of the Canadian wilderness," said Dejardin.

Thomson's "The Jack Pine" (1916-1917), which will appear in the exhibition, has been described as the Canadian Mona Lisa.

"COMMISSION OF THE CENTURY"
The Picture Gallery was established in 1811 when art collector Sir Francis Bourgeois died in a riding accident on Dulwich Common, leaving in his will a collection he had amassed with his business partner Noel Desenfans to Dulwich College, a boys' school on the outskirts of London.

The pair had won the "commission of the 18th century," according to Dejardin, when in 1790 they were asked by the King of Poland to form a royal collection from scratch.

However, during the five years they devoted to creating the collection the Polish monarch was forced to abdicate and the independent state of Poland ceased to exist. They were left with a national collection and no one to claim it.

"The whole thing was supposed to go to Warsaw," said Dejardin. "Thankfully for us it all wound up in a rather dramatic fashion. It never went to Warsaw simply because Poland ceased to exist - Catherine the Great saw to that."

Virtually overnight, Dulwich College became the owner of one of the finest collections of old masters in the world. In 1994 the gallery became independent from the school and shortened its name to the current Dulwich Picture Gallery.