Unpublished texts by Ernest Hemingway about the hunt for German U-boats off the Cuban coast during the Second World War are part of an important collection of the writer’s works to be released next week.

While serving on a ship tracking Nazi submarines in the Gulf of Mexico, Hemingway wrote in code about his exploits.

The notes are among 3,000 letters and other writings by the Nobel laureate to be made accessible online from Monday by curators at the writer’s former residence in Cuba, where he lived from 1939 to 1961.

Scholars and fans hoping to read some unpublished fragments of stories may be disappointed as curators at the Finca VigÍa museum in Havana say that there are not known to be any new literary texts in the collection. Among the array of documents, though, they may find clues to some previously unexplained chapters in Hemingway’s colourful life.

The collection includes the epilogue of For Whom the Bell Tolls and the screenplay for The Old Man and the Sea. Inaurys Portuondo, the museum’s digital specialist, said: “This is an exquisite selection. There are no unedited literary [pieces], at least as far as we know, but we know that specialists might be able to come up with new theories after consulting the archive.”

After the United States entered the Second World War in 1941, Hemingway joined in efforts to hunt German submarines threatening shipping off Cuba and the US. Ada Rosa Alfonso, the Finca VigÍa curator, said that the documents relating to U-boats could serve to “corroborate Hemingway’s theory that they were refuelling in the north of the island”.

The release of the Hemingway archive is part of a joint project between the Cuban National Cultural Heritage Council and the US Social Science Research Council.

As Cuba celebrated the 50th anniversary of the revolution yesterday, the Hemingway project marked a warming of relations between two countries that have been at loggerheads ever since. An expectation is growing that Raúl Castro, the Cuban President, may hold talks with Barack Obama, the US President-elect.

Next month, the newly released documents will be transferred to the John F. Kennedy Presidential Library in Boston. Hemingway aficionados believe that any new material will prove valuable to scholars. James Campbell, an author of books on American literature, said: “Hemingway was one of the major writers of the 20th century, so almost anything is of interest.”

Mary Welsh, Hemingway’s widow, donated Finca VigÍa to the Cuban Government to fulfil the writer’s wishes after he committed suicide in 1961. The collection at Finca VigÍa contains 22,000 items including books, letters and papers, as well as half-finished bottles of gin and whisky.

The writer, the baby shoes

— Ernest Hemingway was born in Illinois in 1899 to a country doctor and an opera singer. He went on to live and work in France, Italy, Canada, Kenya, Tanganyika, Spain, Cuba and Florida

— Apart from journalism and fiction writing, Hemingway tried his hand as a First World War ambulance driver, bullfighter and game hunter

— Married four times, he also fell in love with Marlene Dietrich, though their relationship was never consummated

— Suffering from alcoholism and lifelong depression, Hemingway committed suicide at the age of 61 by shooting himself

— He once said that his best work was only six words long: “For sale: baby shoes, never worn”

Sources: Times archive, Columbia Encyclopaedia, The Oxford Companion to United States History

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