The treasure trove of almost 1,000 documents, collected over 30 years by an Austrian banker, included letters written by Winston Churchill, Peter the Great, Alexander Pushkin, John Donne and Queen Elizabeth I.
The auction proceeds almost doubled pre-sale expectations.
One of the rarest and most touching items in the collection was a passionate letter written by an apologetic Napoleon to his wife-to-be, Josephine de Beauharnais, the morning after a furious argument.
The letter sold for 276,000 pounds, a record for a Napoleon letter and more than five times its pre-sale estimate of 30,000 to 50,000 pounds, auctioneers Christie's said yesterday.
''I send you three kisses one on your heart, one on your mouth and one on your eyes,'' wrote the chastened lover in a spidery scrawl full of corrections and crossings out.
Napoleon was believed to have provoked the quarrel by inquiring about Josephine's wealth held in family estates in the West Indies.
The letters covered more than 500 years and ranged across art, science, literature and philosophy.
''To get a collection of letters like this nowadays is really a one off, it's almost unheard of,'' Thomas Venning, director in Christie's books department, told Reuters.
Owner Albin Schram, who died in 2005, had begun amassing the archive in the early 1970s.
Though an inveterate collector, Schram was not interested in conservation or display the letters were kept in an old metal cabinet in the laundry room of his villa in Lausanne, Switzerland, ordered by size rather than author or date.
A manuscript in which English scientist Sir Isaac Newton discusses the theory of gravity and the structure of the universe, sold for 204,000 pounds compared with a pre-sale estimate of 30,000 to 50,000 pounds.
Another prized lot, a note by metaphysical poet John Donne to Lady Kingsmill a day after the death of her husband in October 1624, sold for 114,000 pounds, within the range estimated before the sale.