Among it is much of the former's private correspondence as well as approximately 250,000 papers and 50,000 photographs of the latter.
Included in the political material, a vital source for those studying the birth of the modern states of India and Pakistan, can be found a handwritten note handed over during a crucial meeting in June 1947 by Mahatma Gandhi, who had taken a vow of silence and so avoided making any comment on the decision to divide the subcontinent.
There are also pictures from the Mountbattens' honeymoon in 1922, when they went to Hollywood to make a film with Charlie Chaplin.
The Broadlands Archives were recently acquired for the university on behalf of the nation in lieu of inheritance tax.
An exhibition titled Everybody Is in Admiration of It: Broadlands, a Country House in Hampshire, can currently be seen in the Special Collections Gallery of the Hartley Library.
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