Schools and colleges should take a more balanced ‘warts and all’ approach to teaching students about the British Empire and colonialism, leading historians have told The Independent.

The calls for better education about the brutality of Britain’s imperial past come amid new research revealing more than four in ten Britons view the British Empire as a good thing and colonialism as something to be proud of.

Only around one in five Britons take the opposite view, seeing Britain’s colonial past as something which should be regretted, according to the YouGov poll released this week.

There is a clear division between Conservative and Labour voters on the issue, with Labour supporters three times more likely, at 30 per cent, to view the colonial past as something which should be regretted, compared to one in ten Tory supporters.

Professor Daniel Branch, head of history, University of Warwick, said: “An unwillingness to engage with the ‘warts and all’ of imperial history makes Britain particularly blind to how governments and the people of other countries view British society.”

Criticism of Britain’s imperial past is seeing Oxford University under pressure to remove a statue of Cecil Rhodes, the Prime Minister of the Cape Colony, who described the English as “the first race in the world.”

On 19 January the Oxford Union voted in favour of having the statue removed. Nicky Morgan, the Education Secretary, commented: “It's a matter for Oxford and for the students to have the debate. But better actually to have a debate about what happened in the past and to realise that we have moved on as a country,” she said.

There is a need for honesty in dealing with Britain’s past, according to Sir Anthony Seldon, vice-chancellor of the University of Buckingham and the former head of Wellington College.

“History teaching should always be honest or it is merely propaganda by powerful interest groups. The history of the British Empire was not all bad, and not all good. Understanding its subtlety and its importance to British and world history is essential for every single student,” he told The Independent.

And Ashley Jackson, Professor of Imperial and Military History, King's College London, commented: “We do need better education...what’s important is that we should understand our past, and that means a warts and all understanding.”

He added: “Understandably a lot of British people would like to think that the imperial past was generally ok, but unfortunately if you look at the record of empire it’s very difficult to say that overall it was a good thing.”

The wealth of the British Empire had a lot to do with exploiting people overseas, according to Professor Jackson. “The basis of empire is that you rule other people, you deny them independence, you exploit their labour and resources, and a lot of the ‘good things’ were often incidental and secondary,” he said.

Dr Andrea Major, associate professor in British colonial history, University of Leeds, is also calling for improved teaching about the British Empire.

There is “a collective amnesia about the levels of violence, exploitation and racism involved in many aspects of imperialism, not to mention the various atrocities and catastrophes that were perpetrated, caused or exacerbated by British colonial policies and actions,” she said.

“We need better education and more open public debate on all aspects of British colonial history 'warts and all' - not as an exercise in self-flagellation, but as a means of better understanding the world around us and how we are perceived by others,” added Dr Major.

And Dr Esme Cleall, lecturer in the history of the British Empire, University of Sheffield, said: “The violence of the British Empire has long been forgotten. We need to face up to this history and education is crucial if we are to do so.”

Yet the subject is largely absent from the curriculum, according to Dr Pippa Virdee, senior lecturer in modern South Asian history, De Montfort University. “Our knowledge of our own history is very limited geographically, let alone giving us any sense of understanding the atrocities that were committed under the imperial gaze.”

She added: “While people are often happy to remember the glorious past, they are reluctant to face the darker side of empire.”

But teaching alone will not change attitudes, commented Dr Christopher Prior, lecturer in 20th Century history, University of Southampton: “Teachers and lecturers can only do so much, when broader cultural forces focus on a positive, benevolent side to Britain’s past.”

He added: “In recent years, there's been lots of public commentary about Britain’s role in ending slavery, but not as much about Britain’s role in having been involved in the slave trade in the first place! We have to be more honest about our imperial heritage, not merely inside the classroom, but outside of it.”

Six shameful aspects of Britain’s past

Slavery

Britain was a key player in the slave trade, with almost half a million slaves in British colonies by the 1790s. And British ships transported up to three million people into slavery in the Americas between 1562 and 1807.

Partition

Up to one million people died in sectarian violence after the border between India and Pakistan was created in 1947. The divide - along religious lines - resulted in more than 14 million people being forced to move. Muslims left India for Pakistan, and Hindus and Sikhs fled their homes in Pakistan to go to India.

Torture

Thousands of Kenyans were beaten, sexually assaulted or raped by British colonial forces during the Mau Mau Uprising in the 1950s. Between 20,000 and 100,000 Kenyans died during the uprising. And in 2013 the British Government paid around £20 million to settle claims made by more than 5,000 Mau Mau veterans.

Famine

Up to 29 million died of starvation in India during British rule, while millions of tons of wheat were exported to Britain. In 1943, up to four million Bengalis starved to death after Winston Churchill diverted food to British soldiers and countries such as Greece, despite there being a famine in Bengal at the time.

Concentration camps

More than 100,000 people were imprisoned in camps during the Boer War in the 19th century. Almost 30,000 Boers died in the overcrowded camps, as well as an unknown number of Africans.

Massacre