Patriotism should be avoided in school lessons because British history is “morally ambiguous”, a leading educational body recommends.

History and citizenship lessons should stick to the bare facts rather than encouraging loyalty to Britain when covering subjects such as the Second World War or the British Empire, the Institute of Education researchers said. Teachers should not instill pride in what they consider great moments of British history, as more shameful episodes could be downplayed or excluded.

The slave trade, imperialism and 20th century wars should be taught as controversial issues while students are deciding how they feel about their country, the report says.

Three quarters of teachers felt obliged to tell students about the danger of patriotism. The survey suggested neither pupils nor teachers wanted patriotism endorsed by schools.

Historians said last night, however, that it was impossible to teach the subject without patriotism or a recognition that British values were rooted in the past.

The report criticises the current drive to use citizenship lessons as a way of promoting pride in being British and developing a sense of belonging. It said: “To love what is corrupt is itself corrupting, not least because it inclines us to ignore, forget, forgive or excuse the corruption. And there’s the rub for patriotism.

“Countries are morally ambiguous entities: they are what they are by virtue of their histories.”

The authors added: “It is hard to think of a national history free from the blights of warmongering, imperialism, tyranny, injustice, slavery and subjugation, or a national identity forged without recourse to exclusionary and xenophobic stereotypes.”

Alan Johnson, the former Education Secretary, announced last year that pupils aged 11 to 16 would have compulsory lessons in British history. Ethnicity, religion, race and national identity will be taught, through studying immigration, the Commonwealth, the Empire and devolution, extending the popular vote and women’s rights.

Gordon Brown said at the time: “There is a golden thread that intertwines the unshakeable British commitment to liberty with another very British idea: that of duty and social responsibility.”

But Dr Hand, the co-author of the report, said: “Gordon Brown and David Cameron have both called for a history curriculum that fosters attachment and loyalty to Britain, but the case for promoting patriotism in schools is weak.

“Are countries really appropriate objects of love? Loving things can be bad for us, for example when the things we love are morally corrupt. Since all national histories are at best morally ambiguous, it’s an open question whether citizens should love their countries.”

The institute - part of the University of London – asked nearly 300 pupils aged 13 to 14, and 47 teachers, in 20 London schools, how patriotism should be handled. About 94 per cent of teachers and 77 per cent of teenagers said that schools should give a balanced presentation of opposing views. Fewer than 10 per cent felt patriotism should be actively promoted.

However, 19 per cent of teachers and 16 per cent of teenagers thought schools should support patriotic views when expressed by pupils.The historian Tristram Hunt said of the institute’s report: “I think it’s a very immature approach to the topic. The point is not whether history was right or wrong from a 21st Century liberal-left perspective. It’s about teaching students to understand the mindset and context of our forebears.

“The real problem isn’t that our children are being indoctrinated with patriotism, but that they don’t know enough British history."

Ambiguous times

1750-1830 The Industrial Revolution: exploitation of the poor versus great wealth creation and growth

1807 Abolition of the slave trade. Britons were both practitioners of the trade and responsible for abolition

1947 Indian independence and Partition. How well did Britain manage its withdrawal from the sub-continent?

2003 Iraq war: was it liberation or occupation?

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