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The UK is marking the 50th anniversary of the death of Winston Churchill. He is regarded by many as the greatest Briton ever, but for some he remains an intensely controversial figure.

During Britain's darkest hours in World War Two, Churchill's leadership was vital in maintaining morale and leading the country to eventual victory over Nazi Germany.

In 2002 Churchill saw off the likes of Shakespeare, Darwin and Brunel to be voted the greatest ever Briton.

But in a career spanning some 70 years, he had more than a few moments of controversy.

"There's a danger in Churchill gaining a purely iconic status because that actually takes away from his humanity," says Allen Packwood, director of the Churchill Archives Centre.

"He is this incredibly complex, contradictory and larger-than-life human being and he wrestled with these contradictions during his lifetime."

Here are 10 of the most common debates that have raged about Churchill's legacy.

Image copyright PA Image caption Paint thrown over Churchill's statue in Parliament Square, 2007

1. Views on race

In April last year, Labour candidate Benjamin Whittingham tweeted that Churchill was "a racist and white supremacist".

Sir Nicholas Soames, Churchill's grandson, was outraged. And Whittingham's Conservative opponent Ben Wallace labelled the comments "ignorant" and "incredibly insulting". The tweet was deleted and the Labour Party said: "[It] does not represent the view of the Labour Party. He apologises unreservedly if it has caused any offence."

But there have previously been suggestions that Churchill held racist beliefs.

In 1937, he told the Palestine Royal Commission: "I do not admit for instance, that a great wrong has been done to the Red Indians of America or the black people of Australia. I do not admit that a wrong has been done to these people by the fact that a stronger race, a higher-grade race, a more worldly wise race to put it that way, has come in and taken their place."

Churchill certainly believed in racial hierarchies and eugenics, says John Charmley, author of Churchill: The End of Glory. In Churchill's view, white protestant Christians were at the top, above white Catholics, while Indians were higher than Africans, he adds. "Churchill saw himself and Britain as being the winners in a social Darwinian hierarchy."

"The mitigation would be that he wasn't particularly unique in having these views," says Richard Toye, author of Churchill's Empire, "even though there were many others who didn't hold them."

Soames thinks it is ludicrous to attack Churchill. "You're talking about one of the greatest men the world has ever seen, who was a child of the Edwardian age and spoke the language of [it]."

And Churchill's views on race were incomparable to Hitler's murderous interpretation of racial hierarchy, Toye says. "Although Churchill did think that white people were superior, that didn't mean he necessarily thought it was OK to treat non-white people in an inhumane way."

Image copyright Getty Images Image caption British RAF armoured cars and bomber planes on duty in Iraq during the Mesopotamia conflict, 1922

2. Poison gas

Churchill has been criticised for advocating the use of chemical weapons - primarily against Kurds and Afghans.

"I cannot understand this squeamishness about the use of gas," he wrote in a memo during his role as minister for war and air in 1919.

"I am strongly in favour of using poisoned gas against uncivilised tribes," he continued.

These quotes have been used by critics such as Noam Chomsky to attack Churchill.

But the controversy is misplaced, says Warren Dockter, a research fellow at the University of Cambridge and the author of Winston Churchill and the Islamic World. "What he was proposing to use in Mesopotamia was lachrymatory gas, which is essentially tear gas, not mustard gas."

Churchill's 1919 memo continued: "The moral effect should be so good that the loss of life should be reduced to a minimum. It is not necessary to use only the most deadly gasses: gasses can be used which cause great inconvenience and would spread a lively terror and yet would leave no serious permanent effect on most of those affected."

In another memo about using gas against Afghans, Dockter says, Churchill questioned why a British soldier could be killed lying wounded on the ground while it was supposedly unfair "to fire a shell which makes the said native sneeze - it really is too silly".

But some still criticise the British air attacks used to quell rebellious tribes in the region.

And it's important to note that he was in favour of using mustard gas against Ottoman troops in WW1, says Dockter, although this was at a time when other nations were using it.

Image copyright Getty Images Image caption Famine-stricken children in India, 1943

3. Bengal famine

In 1943, India, then still a British possession, experienced a disastrous famine in the north-eastern region of Bengal - sparked by the Japanese occupation of Burma the year before.

At least three million people are believed to have died - and Churchill's actions, or lack thereof, have been the subject of criticism.

Madhusree Mukerjee, author of Churchill's Secret War, has said that despite refusing to meet India's need for wheat, he continued to insist that it exported rice to fuel the war effort.

"[The War Cabinet] ordered the build-up of a stockpile of wheat for feeding European civilians after they had been liberated. So 170,000 tons of Australian wheat bypassed starving India - destined not for consumption but for storage," she said upon release of the book in 2010.

Churchill even appeared to blame the Indians for the famine, claiming they "breed like rabbits".

"It's one of the worst blots on his record," says Toye. "It clearly is the case that it was difficult for people to get him to take the issue seriously."

"Churchill viewed it as a distraction," he explains. Preoccupied with battling Germany in Europe, Churchill didn't want to be bothered by it when people raised the issue.

"We have this image of Churchill being far-sighted and prophetic," says Charmley. "But what he does tragically in the case of the Bengal famine is show absolutely zero advance [since] the Irish famine 100 years earlier."

It was a horrendous event but it needs to be seen within the context of global war, says Packwood.

"Churchill is running a global war at this point and there are always going to be conflicting priorities and demands," he says. "It's an incredibly complex and evolving situation - and he's not always going to get everything right."

Arthur Herman, author of Gandhi & Churchill, has argued that without Churchill the famine would have been worse. Once he was fully aware of the famine's extent, "Churchill and his cabinet sought every way to alleviate the suffering without undermining the war effort", Herman wrote.

It was a failure of prioritisation, says Toye. It's true that Britain's resources were stretched, he says, but that's no excuse given the relatively small effort it would have taken to alleviate the problem.

Image copyright Getty Images Image caption Churchill on Gandhi: "A seditious lawyer, posing as a fakir"

4. Statements about Gandhi

Churchill had strong views on the man now widely respected for his work in advocating self-determination for India.

"It is alarming and nauseating to see Mr Gandhi, a seditious Middle Temple lawyer, now posing as a fakir… striding half-naked up the steps of the Vice-regal Palace," Churchill said of his anti-colonialist adversary in 1931.

"Gandhi should not be released on the account of a mere threat of fasting," Churchill told the cabinet on another occasion. "We should be rid of a bad man and an enemy of the Empire if he died."

It's unfashionable today to question Gandhi's non-violent political tactics. He is venerated in much the same way as Churchill is in the UK. But for years he was a threat to Churchill's vision for the British Empire.

"He put himself at the head of a movement of irreconcilable imperialist romantics," wrote Boris Johnson in his recent biography of Churchill. "Die-hard defenders of the Raj and of the God-given right of every pink-jowled Englishman to sit on his veranda and… glory in the possession of India."

"Churchill was very much on the far right of British politics over India," says Charmley. "Even to most Conservatives, let alone Liberals and Labour, Churchill's views on India between 1929 and 1939 were quite abhorrent."

He was vociferous in his opposition to Gandhi, says Toye, and didn't want India to make any moves towards self-government to the extent of opposing his own party's leaders and being generally quite hostile to Hinduism.

Churchill's stance was very much that of a late Victorian imperialist, Charmley adds. "[Churchill] was terribly alarmed that giving the Indians home rule was going to lead to the downfall of the British Empire and the end of civilisation."

Younger Tories like Anthony Eden regarded Churchill with great mistrust during the 1930s because of his association with hard-line right-wingers in the party, he says.

"People sometimes question why on Earth did people not listen to Churchill's warnings about Hitler in the late 1930s," says Charmley, "to which the short answer is that he'd used exactly the same language about Gandhi in the early 1930s."

5. Attitudes towards Jews

In 2012 there were objections to a proposed Churchill Centre in Jerusalem on the basis that he was "no stranger to the latent anti-Semitism of his generation and class".

Sir Martin Gilbert, Churchill's official biographer, countered that "he was familiar with the Zionist ideal and supported the idea of a Jewish state".

But being anti-Semitic and a Zionist are not incompatible, says Charmley.

"Churchill with no doubt at all was a fervent Zionist," he says, "a fervent believer in the right of the Jewish people to a state of their own and that state should be in what we then called Palestine."

But he also "shared the low-level casual anti-Semitism of his class and kind", he says. If we judged everyone of that era by the standards of 21st Century political correctness, they'd all be guilty, he notes. "It shouldn't blind us to the bigger picture."

A 1937 unpublished article - supposedly by Churchill - entitled "How the Jews Can Combat Persecution" was discovered in 2007. "It may be that, unwittingly, they are inviting persecution - that they have been partly responsible for the antagonism from which they suffer," it said. "There is the feeling that the Jew is an incorrigible alien, that his first loyalty will always be towards his own race."

But there was immediately a row over the article, with Churchill historians pointing out it was written by journalist Adam Marshall Diston and that it might not have represented Churchill's views at all accurately.

"Casual anti-Semitism was rampant," agrees Dockter, "[but] it's inconceivable to pitch him as anti-Semitic."

In a 1920 article, he wrote: "Some people like Jews and some do not; but no thoughtful man can doubt the fact that they are beyond all question the most formidable and the most remarkable race which has ever appeared in the world."

Winston Leonard Spencer Churchill, 1874-1965

Image copyright PA

Born 30 November 1874 at Blenheim Palace in Oxfordshire. Attended Harrow and Sandhurst before embarking on army career, seeing action in India, and Sudan

Became Conservative MP in 1900, but in 1904 joined the Liberal Party. Cabinet member from 1908, he was First Lord of the Admiralty from 1911 until the disastrous Dardanelles expedition in early part of WW1. Served on Western Front for a time, before rejoining government from 1917-1929

Opposition to Indian self-rule, warnings about the rise of the Nazis and support for Edward VIII left Churchill politically isolated during 1930s. After WW2 broke out, he replaced Neville Chamberlain as prime minister, where his reputation as inspirational wartime leader was cemented

Lost power in 1945 election but was returned to power in 1951, and continued as prime minister until 1955. Died 24 January 1965 and was given a state funeral

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6. Attitudes towards Islam

Paul Weston, chairman of the Liberty GB party, was arrested last year on suspicion of racial harassment after reading aloud some of Churchill's thoughts on Islam.

Weston was quoting from Churchill's 1899 book The River War, in which he wrote: "How dreadful are the curses which Mohammedanism lays on its votaries! Besides the fanatical frenzy, which is as dangerous in a man as hydrophobia [rabies] in a dog, there is this fearful fatalistic apathy.

"Improvident habits, slovenly systems of agriculture, sluggish methods of commerce and insecurity of property exist wherever the followers of the Prophet rule or live."

Snippets of these quotes now accompany Churchill's face in numerous internet memes purporting to show his anti-Islam stance.

"That was probably the most common view shared by British people of Churchill's era and I've no doubt that he believed exactly that," says Charmley.

But Churchill had a much more nuanced stance on Islam, Dockter says. The 1899 book was written in specific reference to the Mahdists of Sudan, immediately following the war there in which Churchill fought.

It was recently revealed that Churchill was sufficiently fascinated with Islam for his family to be concerned at one point that he might convert.

And in 1940, his cabinet set aside £100,000 for the construction of a mosque in London in recognition of the Indian Muslims who fought for the British Empire. He later told the House of Commons: "Many of our friends in Muslim countries all over the East have already expressed great appreciation of this gift."

"His relationship with Islam is far more complex than most people realise," Dockter suggests, noting that Churchill went on holiday to Istanbul and played polo in India with Muslims.

Image copyright Getty Images Image caption Striking miners in Tonypandy, 1910

7. Treatment of strikers

Churchill's reputation as being anti-union primarily stems from an incident in 1910.

His handling of the Tonypandy Riots that year was the source of much controversy and invited ill-feeling towards him in south Wales for the rest of his life.

His grandson even had to defend Churchill's actions as late as 1978, when Prime Minister James Callaghan referenced "the vendetta of your family against the miners of Tonypandy".

The riots had erupted in November 1910 in the south Wales town because of a dispute between workers and the mine owners, culminating in strikes that ultimately lasted almost a year.

When the strikers clashed with local police, Churchill - then home secretary - sent in soldiers.

Allegations that shots were fired by the soldiers were unfounded, explains Toye. In fact he'd sent a memo expressly denying that the use of violence was a possibility.

Yet it made him a "pantomime villain" in the area ever since, Louise Miskell, a historian at Swansea University, told the BBC in March 2014.

But a year later soldiers were again called in, this time to strike-related riots in Liverpool. On this occasion the soldiers did fire their weapons and two people were killed.

And in later years his contempt for unions became more pronounced, says Charmley.

In 1919, under Churchill, by now Secretary of State for Air and War, tanks and an estimated 10,000 troops were deployed to Glasgow during a period of widespread strikes and civil unrest amid fear of a Bolshevist revolt.

The Tonypandy incident is comparable to Margaret Thatcher's later struggles with miners, Charmley suggests. One could argue that had Churchill not moved in troops the situation could have been much worse and he would have been criticised even more, he says.

In Boris Johnson's biography, he promotes the more liberal side of Churchill as the "begetter of some of the most progressive legislation for 200 years".

"Together with [former PM David] Lloyd George, he deserves the title of Founder of the Welfare State."

Image copyright Getty Images Image caption David Lloyd George and Winston Churchill, 1915

He supported quite radical social reform, adds Packwood, but it was more in the form of Victorian paternalism and he was a die-hard opponent of communism who saw the hand of it behind the Labour movement during the 1920s.

"For someone who has this terrible reputation with the unions," says Packwood, "he actually goes on to run two very conciliatory governments."

Image copyright Getty Images Image caption Winston Churchill (in top hat, centre left) during the Sidney Street siege of 1911

8. Sidney Street siege

Not long after the Tonypandy Riots, Churchill was under fire for rash involvement of a different sort.

The siege of Sidney Street was a gunfight in London's East End in January 1911. Some 200 police surrounded the hideout of a gang of Latvian anarchists led by "Peter the Painter", who had killed three policemen the month before.

A long gun battle ended with the deaths of two of the gang, after Churchill had ordered firefighters not to put out the burning building they'd been hiding in until the shooting had stopped.

But the controversy for Churchill arose from the appearance that he'd been issuing orders and directly meddling in police operations.

Arthur Balfour told the Commons: "He and a photographer were both risking valuable lives. I understand what the photographer was doing but what was the right honourable gentleman doing?"

For Churchill's opponents it was an example of rashness and instability, says Toye. A newsreel film had caught him in the midst of the action.

A contemporary wrote in a letter that "I do believe that Winston takes no interest in political affairs unless they involve the chance of bloodshed", explains Charmley.

"Churchill liked a photo opportunity before the word had been invented," says Charmley.

Image copyright Getty Images Image caption The "Black and Tans" (pictured in Tipperary, 1921) gained a reputation for excessive violence

9. Role in Ireland

In January 1919 Churchill assumed the role of Secretary of State for War and Air. Eleven days later the Irish War of Independence began.

Churchill's role in Ireland is most associated with deploying the controversial "Black and Tans" to fight the Irish Republican Army (IRA). Named after their uniforms, these temporary constables soon developed a reputation for excessive violence.

In Churchill: The Greatest Briton Unmasked, Nigel Knight claims that Churchill repeatedly refused to stand down the Black and Tans and even advocated the use of air power in Ireland.

But it would be unfair to label Churchill as anti-Irish, says Toye.

Although Churchill was against home rule for Ireland and initially implemented harsh repression, he was also an early advocate of partition, Toye explains. Churchill played a key role in the Anglo-Irish Treaty of 1921, which ended the war.

"It comes back to his character, which is: 'In war, resolution, in peace, magnanimity'," says Packwood. "When he felt that there was a fight he would push very hard [and] when he thought there was a chance of peace and dialogue he was also at the forefront of that."

Churchill had expressed support for home rule as early as 1912.

He also recognised the role that Irish personnel serving in the British armed forces played in both WW1 and later in WW2, adds Toye.

10. Cash for influence

"In return for a fee of £5,000 two oil companies, Royal Dutch Shell and Burmah Anglo-Persian Oil Company [later BP], asked him to represent them in their application to the government for a merger," Gilbert's official biography stated.

By modern British political standards, the 1923 payment would be considered highly inappropriate.

Churchill, whose "political career was in the doldrums" at the time, according to a history of British Petroleum, agreed to use his parliamentary influence to raise the issue in return for money.

"But I'd be careful about calling it a bribe," Toye says. "He accepted all sorts of gifts, which in today's culture of full disclosure would get you expelled from the Commons. But those rules were not in place at the time."

The Register of Members' Interests was introduced in 1975. "You can argue that it was a conflict of interest, you can even argue that it was wrong, but you can't call it a bribe in the sense that it was actually illegal," Toye says.

"Politicians' links with business and the media weren't under the same level of scrutiny as they were then," says Packwood, "he was operating in a slightly different ethical environment."

More on Churchill

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