Tributes have been paid to Australia's former prime minister Gough Whitlam who died on Tuesday at the age of 98.
Tony Abbott, the country's current PM, said he was a "giant of his time" while opposition leader Bill Shorten said he "changed the lives of a generation".
Mr Whitlam ended 23 years of conservative rule in 1972 and introduced a host of reforms including establishing universal health care.
He was sacked by the governor-general in 1975 after a constitutional crisis.
"He united the Australian Labor Party, won two elections and seemed, in so many ways, larger than life," Mr Abbott said in a statement.
He instructed flags to fly at half-mast across Australia on Tuesday as a mark of respect.
Mr Shorten echoed Mr Abbott's comments, saying: "I think it is fair to say, regardless of one's politics, the nation has lost a legend."
"Gough Whitlam redefined our country and in doing so he changed the lives of a generation," Mr Shorten added.
Wendy Frew, Australia editor, BBC Online
It is difficult to overestimate the influence of Gough Whitlam on the Australian political and civic landscape.
A giant both physically and politically, his vision for a modern Australia was loved and loathed in almost equal measure. He spent less than three years in office but much of the legacy of his government's reforms remains today.
His achievements range from those on the international stage - he was one of the early few to openly advocate for Australian and international recognition of communist China - to the more pedestrian such as connecting all houses in Australia's capital cities to sewerage.
Along the way, his government managed to shake-up conservative, white Australia by reforming family law, moving to equal pay for women and starting what would turn out to be a very long process of entrenching in law Aboriginal land rights.
He tackled the nation's cultural cringe too by introducing Australia's own honours system and introducing free access to universities, which saw a wave of people become the first in their families to receive higher education.
Communications Minister Malcolm Turnbull, who was Mr Whitlam's MP, called him a "big man with a big vision for a big country".
While Mr Whitlam's decisions, including his economic agenda, were controversial, "all of that recedes... What people remember of Gough Whitlam is a bigness, a generosity, an enormous optimism for Australia, and that is something we can all subscribe to," he said in parliament.
Mr Whitlam's raft of reforms included introducing free university education, abolishing the death penalty and allowing non-white immigrants into Australia.
He was also the first Australian leader to visit China, establishing diplomatic relations with what is now Australia's largest trading partner. Mr Abbott said this was "an enduring legacy".
He led Labor to its historic victory in December 1972 on the back of the famous "It's time" campaign to move on from a post-war period of social conservatism.
His dismissal just three years later was prompted by a refusal by parliament's upper house, where Labor did not hold a majority, to pass a budget bill.
To end the crisis, Governor-General Sir John Kerr dismissed Mr Whitlam in December 1975 and installed opposition leader Malcolm Fraser as the caretaker prime minister.
He remains the country's only prime minister to have been sacked.
Mr Fraser tweeted on Tuesday that Mr Whitlam was "a great Australian".
After leaving politics, Mr Whitlam served as a Unesco ambassador, academic and after-dinner speaker and regularly appeared at Labor Party functions.
He had four children with his wife, Margaret, during a marriage that lasted 70 years until her death in 2012 at the age of 92.
His family said there would be a private cremation and a public memorial service.