The personal archive of World War I poet Siegfried Sassoon has arrived at Cambridge University, marking the culmination of a successful fundraising campaign by the University Library which raised £1.25 million to buy the collection.

Hailed as “extraordinary”, the archive includes war diaries kept by Sassoon on the Western Front and in Palestine between 1915 and 1918, alongside schoolboy notebooks, love letters and early drafts of his most famous works.

One of the most treasured features is a manuscript of ‘A Soldier’s Declaration’ - the 1917 statement written by the poet detailing his refusal to return to war after being wounded. In it, he claimed that the War was being “deliberately prolonged” by those in power.

The Library was able to buy the collection following a successful fundraising drive, helped by a £550,000 grant from the National Heritage Memorial Fund. Other substantial donations were made both by organisations and private individuals.

University Librarian Anne Jarvis said: “We are delighted to have secured the future of the Sassoon archive, and to be able to make these extraordinary documents available in the University Library. The outcome is a source of both satisfaction and excitement to all those who have worked so hard to make it possible.”

The archive had been in the possession of Sassoon’s son until his death in 2006. When it came on the market last year, the University Library was immediately identified as a suitable home. It has for many years been a leading institution in the preservation of his manuscripts and letters. The combination of the Library’s existing holdings with the new archive has created the world’s foremost resource for the study of Sassoon’s works.

The news has been welcomed by many. Author Sebastian Faulks, known for his First World War novel, ‘Birdsong’, applauded the purchase as “a major coup for Cambridge University”, stating that “the papers will be of huge benefit to scholars both of literature and of history.”

The former Poet Laureate Sir Andrew Motion said that it was “wonderful news”, adding that the archive is of “the greatest importance, nationally and internationally.”

Max Egremont, Sassoon’s biographer and leader of the campaign, stated in November 2009 that it would be “particularly appropriate” if the documents were to be kept at the University. Sassoon studied Law as an Undergraduate at the University, before dropping out in 1907. He latterly became an Honorary Fellow of Clare College.

The archive is to be sorted and catalogued by the University Library’s staff. A major display of the Sassoon collections will open in the Library’s Exhibition Centre in July 2010.

Exhibitions Officer John Wells said: “Everyone who sees these documents is thrilled by the vital immediacy and poignancy of the meaning they convey. We can hardly wait to put them on show to the public”.