It was the most brutal cabinet reshuffle in British political history. Fifty years ago Prime Minister Harold Macmillan shocked the nation by sacking seven ministers in what became known as the 'Night of the Long Knives'. But does the legend give the full story and are there parallels with today?

"What happened in 1962 is off the scale of all ministerial changes under virtually any prime minister because it's a third of the cabinet," according to Peter Caterall, editor of Macmillan's private diaries.

While the events were unprecedented, this sacking of so many senior colleagues was also believed to be out of character for Macmillan.

But he was a prime minister under pressure.

As the sixties progressed, the once popular Macmillan began to fear his Conservative party was in meltdown.

The arrival of the youthful and charismatic John F Kennedy as president of the United States made many elderly members of the government look out of touch in a rapidly changing Britain.

With a badly ailing economy and the loss of a supposedly safe by-election, many senior figures in the party joined in the panic.

Image caption Was the indiscretion of Rab Butler (right with Macmillan) a deliberate ploy?

"I did feel strongly Macmillan was losing his grip on public opinion and the party in general," said Conservative peer Lord Hailsham, speaking in 1989.

"The party had lost its sense of direction and conviction and this was due to neglect from the centre. Party inspiration is at the centre of electoral success and without electoral success you don't win elections."

The final straw for Macmillan came with defeat in the once safe Tory seat of Orpington in a by-election in April 1962. He became convinced of the need to act.

Macmillan had lost faith in several members of his cabinet, including his high-profile colleague and friend, Chancellor Selwyn Lloyd, noting in his diaries that his chancellor "did not have the appearance of a man with fire in his belly."

Macmillan discussed matters with Iain Macleod, Leader of the House of Commons and Home Secretary Rab Butler and an orderly reshuffle was planned for autumn 1962.

However, the plans were soon splashed on newspaper front pages after Butler spoke indiscreetly with a journalist.

Macmillan believed the conversation part of a deliberate ploy by the ambitious Butler.

The leak forced Macmillan's hand and he acted swiftly, sacking Lloyd that evening and six other cabinet members the next day - Friday 13 July - calling them to his office one by one to confirm the news.

Find out more Listen to Peter Oborne on Radio 4's Archive on 4 - The Night of the Long Knives on Saturday 7 July at 20:00 BST

Peter Oborne is a political commentator and columnist

Macmillan believed he had acted honourably and without malice toward his chancellor.

"I don't like the expression sacked. I prefer replaced. But I thought in the new economic situation we wanted a less tired mind," Macmillan said years later.

"Selwyn had been a splendid minister for a solid eight years. I felt he was not creative any more, therefore I wanted a new man at the Treasury and a younger man."

Selwyn Lloyd took a different view.

"He has given his own explanation that I was tired out. I personally didn't feel at all tired, I thought things were going rather well."

"It just shows in politics you should always be ready for the unexpected," said Lloyd later.

"It's very unpleasant, especially as it has to be done in this abrupt way. Otherwise there is no authority at the top of government," said Macmillan speaking of the events in 1971.

But the country and Westminster were stunned by the speed and scale of events.

Such political brutality was not in keeping with Macmillan's gentlemanly image.

The reshuffled Selwyn Lloyd, Chancellor replaced by Reggie Maudling

David Maxwell Fyfe, Lord Chancellor replaced by Reginald Manningham-Buller

David Eccles, Minister of Education replaced by Edward Boyle

Harold Watkinson, Minister of Defence replaced by Peter Thorneycroft

John Scott Maclay, Secretary of State for Scotland replaced by Michael Noble

Charles Hill, Minister of Housing replaced by Keith Joseph

Percy Mills, Minister without Portfolio replaced by William Deedes

The then-rising political star of the Liberal Party, Jeremy Thorpe, famously summed up the mood in Westminster when he said "greater love hath no man than this - that he lay down his friends for his life."

"I am not easily persuaded of the sorrow in the heart of a butcher", said Conservative MP Enoch Powell, also unconvinced by Macmillan's remorse.

"There's a certain zest about the job. I dare say Henry VIII might have told you afterwards how much he regretted sending people to the block."

During his early years as prime minister, Macmillan had been nicknamed "Supermac", but as public opinion swung against him, he acquired a new nickname - "Mac the knife".

In Parliament the following week, Lloyd was cheered by MPs. Macmillan was greeted with silence.

The Night of the Long Knives has gone down in history as a textbook political disaster, but others believe except for Butler's careless talk it may have been seen as a masterstroke of political renewal.

"Focus on the new names that Macmillan brought in," says political commentator Peter Oborne.

"He had hand-picked many of the resonant figures who would shape the future of the Conservative Party, while for the most part he had sacked a collection of deadbeats and non-entities."

"This was the new generation - Reggie Maudling, Keith Joseph, Peter Thorneycroft - average age just 50, compared to the average of 59 for the seven departed cabinet ministers," said Oborne.

Image caption Selwyn Lloyd was brought back into government in 1963 by new Prime Minister Alec Douglas-Home

"Macmillan was trying to demonstrate the Conservatives were capable of grasping modernity which is why he wanted to bring in some of these younger people," Caterall told the BBC.

However, fallout over the manner of the reshuffle saw Macmillan's popularity continue to sink.

The veto by French president De Gaulle against Britain's membership of the EEC in early 1963 which damaged prospects of economic growth and the scandal of the Profumo affair dealt further shattering blows to Macmillan's government.

A health scare in autumn of 1963, gave Macmillan the opportunity to bow out as prime minister.

But the Night of the Long Knives should not just be viewed as a history lesson, according to some.

"David Cameron is an admirer of Harold Macmillan. There is quite a lot of similarity in that both went to Eton and Oxford," said Professor Vernon Bogdanor of Kings College London.

"We have a Macmillanite prime minister in David Cameron.

"He is an instinctive Conservative, as Macmillan would have said, a One Nation Conservative trying to reach out to people who don't normally support the Conservatives.

"When Cameron became leader in 2005, he said he wanted to modernise the Conservatives. That's what Macmillan did," Bogdanor concludes.

Oborne sees further parallels between the events of 1962 and today.

"Like Macmillan, Cameron's lustre is fading. He too faces grave economic problems allied to falling support in the polls and is believed to be planning to revitalise his administration with a reshuffle," said Oborne.

"It is important Cameron does not let the legacy of the 'Night of the Long Knives' inhibit his own political calculations."