Editor of new unexpurgated edition of controversial author's work claims it reveals him as brilliant war poet who attacked British imperialism

DH Lawrence was an infamous victim of the censor as his sexually explicit novel Lady Chatterley's Lover was banned in Britain until 1960. Now a new edition of Lawrence's poems, many rendered unreadable by the censor's pen, will reveal him as a brilliant war poet whose work attacking British imperialism during the first world war was barred from publication.

His poems took aim at politicians, the brutality of the first world war and English repression – but censorship and sloppy editing rendered them virtually meaningless, to the extent that the full extent of his poetic talent has been overlooked.

Deleted passages have now been restored and hundreds of punctuation errors removed for a major two-volume edition to be published on 28 March by Cambridge University Press – the final part of its mammoth 40-volume edition of Lawrence's Letters and Works.

The Poems, the first critical edition of Lawrence's poetry, sheds new light on the miner's son who became one of the 20th century's most influential writers, with novels such as Sons and Lovers, The Rainbow and Women in Love.

The new volume's editor, Christopher Pollnitz, told the Observer that it "radically shifts our understanding of Lawrence's significance as a poet". What was removed from the poems – by state censors or publishers fearing government intervention – was the "ultimate censorship", he said, because extensive and significant cuts made the texts virtually unreadable.

Lawrence wrote poetry from 1905 until his death in 1930, aged 44. Pollnitz said it is widely assumed that only the novels suffered censorship, "but it goes all through the poetry as well".

Some 860 poems are published in the new edition. They include All of Us, a sequence of 31 war poems never fully published before, which reveal Lawrence's preoccupation with the Allies' campaigns in the first world war.

Between 1916 and 1919, Lawrence struggled to get the sequence into print. Pollnitz said publishers who knew of the banning of The Rainbow would not touch a collection that criticised imperial policy – the opening up of eastern fronts in Turkey or Iraq – and poetry that explored the evil of self-sacrifice for some abstract greater good.

Lines now restored identify places such as Salonika and Mesopotamia – explosive references at the time, Pollnitz said. "While the war was continuing, the worst defeat the British suffered was in Mesopotamia … General Townshend's charge up the Tigris towards Baghdad was one of the most costly and wasteful ventures, in lives and money, of the first world war."

The subtitle Salonika appears in Rose, Look out upon Me, a previously unpublished work. Pollnitz said: "Salonika was the Greek city to which Allied troops were sent after the attempt to storm the Dardanelles failed."

In the poem, Lawrence portrayed a common English soldier, stationed in Salonika, who is attracted to a Greek woman, but it is a doomed passion: "Oh you Rose, look out/ On a miserable weary fellow./ For once she looked down from above/ And vanished again like a swallow/ That appears at a window …"

Lawrence also wrote about the home front, and the changing roles of women – a girl startling her boyfriend by asking him to stay with her before he leaves – and how childhood innocence can be wrecked by the stresses of war.

Pollnitz added: "Lawrence's writing on war and sex were censored by publisher timidity, making All of Us unpublishable at the time, and the sequence is being fully published almost 100 years after its wartime composition."

Ill-health meant Lawrence himself was never conscripted. His insight into the war probably came from his pacifist friend, Lady Cynthia Asquith, daughter-in-law of prime minister Herbert Asquith. While war poets such as Wilfred Owen depicted the cruelty of a bloody battlefield, Lawrence tackled the loss of lives and impact on loved ones from a political point of view. He also had to write with more subtlety because censors were already watching him. In a poem titled Dust, he wrote of a relative's horrible death: "My brother died in the heat/ And a jackal found his grave;/ Nibbled his fingers, the knave;/ No more would I let him eat."

In Antiphony, he wrote of a British prisoner of war in Turkey struggling to cope with captivity – "Each evening, bitter again" – and, in Needless Worry, he explored a young woman's loss of her soldier fiancé, talking to her mother: "Why are you so anxious, there's no fear now he's dead."

In The Well of Kilossa, he referred to the war in German east Africa and the huge loss of lives in inhospitable terrain: "A draught of thee is strength to a soul in hell."

The poetry edition is published a century after 10,000 words were censored from Sons and Lovers, and nearly all copies of The Rainbow destroyed, with a sexual episode between Ursula Brangwen and her schoolmistress among offending passages. His sexually explicit 1928 novel, Lady Chatterley's Lover, became a cause célèbre in 1960 when, after a much-publicised trial, Penguin won the right to publish the complete book – a dramatic step towards securing freedom of the written word.

 © Guardian News and Media 2013