The world-renowned and much-loved physicist was embroiled in a fierce legal battle with Health Secretary Jeremy Hunt, over a health service shakeup he had condemned.
Hawking was also a lifelong Labour supporter, although he called for Jeremy Corbyn to step down before last year’s general election – saying: “I regard Corbyn as a disaster.
“His heart is in the right place and many of his policies are sound, but he has allowed himself to be portrayed as a left-wing extremist. I think he should step down for the sake of the party.”
However, at an election event in his home city of Cambridge, the scientist also said: “I’m voting Labour because another five years of Conservative government would be a disaster for the NHS, the police and other public services.”
The Labour leader tweeted his tribute today, saying: “Stephen Hawking inspired the world with his determination to explain the mysteries of the cosmos. But he also showed breathtaking courage to overcome life's adversities and a burning passion to protect our National Health Service. He will be greatly missed.”
The war of words with Mr Hunt blew up over the creation of accountable care organisations (ACOs), bringing most of a local area’s NHS services under one budget, run by a single organisation.
Critics fear they will be a “Trojan horse” for greater privatisation, their suspicions aroused because they are modelled on identically named health organisations in the US.
Last year, Hawking accused the Conservatives of responsibility for the NHS's deep problems, by starving it of cash – and Mr Hunt of misrepresenting research findings to make his case.
“I am concerned that accountable care organisations are an attack on the fundamental principles of the NHS,” he warned.
“They have not been established by statute, and they appear to be being used for reducing public expenditure, for cutting services and for allowing private companies to receive and benefit from significant sums of public money.”
He joined an ongoing campaign for High Court judges to grant a judicial review to stop the Government and NHS England bringing in ACOs without proper scrutiny by Parliament.
In response, Mr Hunt described Hawking as a “personal hero” to him but insisted he was wrong to claim the NHS was heading towards a “US-style insurance system”.
On Twitter, the Health Secretary accused him of making arguments with a “lack of evidence” later criticising the scientist was spreading “pernicious falsehoods”.