Australian Labor is mourning the death of Simon Crean, a regional political legend and a Labor prince who never became king.
The former party leader has been remembered as a giant of Australian politics, following his sudden death in Germany aged 74.
His family said they were devastated after he died on Sunday morning following an exercise session in Berlin, where he was part of an industry delegation.
"Simon was a fierce advocate for working Australians and dedicated his life to making a difference," the Crean family said in a statement.
Mr Crean served as the Hotham MP from 1990 to 2013 and held several regionally-oriented portfolios. In the Hawke and Keating governments, he served as Primary Industries and Energy Minister, and Trade and Regional Development Minister under the Gillard government.
National Farmers' Federation president Fiona Simson said Mr Crean was a "remarkable man" who commanded the respect of the agriculture industry.
"He played a significant role in shaping agricultural policies and was a strong advocate for agriculture, for farmers and for free trade, both during and after his political career," Ms Simson said.
"Simon actively supported the Landcare movement to encourage sustainable land management practices and championed the involvement of farmers and local communities.
"Simon's efforts have contributed to the advancement of agriculture and the promotion of sustainable development in Australia's regional areas and for this, he leaves a legacy that will be remembered by farmers."
Mr Crean was instrumental in establishing the Regional Australia Institute borne out of a commitment by the Gillard Government to regional crossbench MPs, Tony Windsor, Rob Oakshott and Bob Katter.
RAI chair Christian Zahra said history would show Mr Crean to be "one of Australia's most effective regional development ministers", who had an ability to connect with people from all walks of life.
"Wherever you went in regional Australia, people had met Simon and liked him and had a story to tell about something he'd done to make a difference in their region," Mr Zahra said.
"He was an excellent listener and always followed through on the things he said he'd do.
"Simon was a true friend of regional Australia. He was a man who clearly saw the growth potential of regional Australia and the need for a nuanced approach to the policy to shape this growth."
After politics, he was elected chairman of the Australian Livestock Exporters Council in 2014, serving in the role for six years. Mr Crean said he felt obligated to help the industry following the Gillard government's 2011 live cattle ban.
Prime Minister Anthony Albanese said Mr Crean made a difference across many areas during his 23-year parliamentary career.
"He was a giant of the labour movement, to rise from being a union official right through to the ACTU presidency, and then to take the skills that he had into the federal parliament and to serve Australia," he told Seven's Sunrise program on Monday.
"He made a significant contribution across four different governments under Hawke, Keating, Rudd and Gillard."
Mr Albanese said a state funeral had been offered to Mr Crean's family, with arrangements being made to bring him back to Australia.
He followed in the footsteps of his father Frank, who served as treasurer in the Whitlam government and as deputy prime minister in the government's last months.
As ACTU vice-president, Mr Crean played a key role in bringing about The Accord between unions and employers in 1983.
Former prime minister John Howard said Mr Crean's loss would be keenly felt throughout the labour movement.
"He was a formidable adversary who I both liked and respected," Mr Howard said.
"Never surrendering his true Labor beliefs, he could work in a bipartisan way when the national interest needed it."
Labor national president Wayne Swan said Mr Crean was a "great Australian".
"Simon's lifelong commitment to the labour movement places him amongst the greats of our party," he said.
Government Services Minister Bill Shorten paid tribute to the former leader's opposition to Australia's involvement in the Iraq War.
"If politics had a hall of fame, like some of our sporting codes do, Simon would be a member," he told ABC TV.
Elected to the Victorian seat of Hotham In 1990, Mr Crean became science minister in the Hawke government.
Narrowly missing out on the Labor deputy leadership after Labor's election loss in 1996, he took on the position two years later after another election defeat.
After a third consecutive defeat in November 2001 he was elected unopposed as leader.
Mr Crean faced continued speculation about a Kim Beazley comeback amid poor opinion poll results and he resigned on the advice of colleagues in November 2003 - becoming the first Labor leader since 1916 to be replaced without having contested an election.
Former prime minister Julia Gillard said Mr Crean dedicated his life to Labor values.
"He hated injustice and fought hard to bring opportunity to all," she said in a statement.
Opposition Leader Peter Dutton said Mr Crean was a gentleman.
"I always admired Simon for his intellect and decency ... A very sad day," he tweeted.
Home Affairs Minister Clare O'Neil, who replaced Mr Crean in the Victorian electorate of Hotham, said he was integral to events in politics and industrial relations for four decades.
"Every step of the way Simon backed me in my career and I saw him doing the same to so many other Labor women," she said.
Former prime minister Tony Abbott paid tribute to "a thoroughly admirable man".
"He never made the mistake of identifying the wellbeing of the country with his own personal advancement," he said in a statement.
After leaving politics, Mr Crean chaired the European Australian Business Council.
Mr Albanese said the hearts of the Labor family went out to Mr Crean's beloved wife Carole, to his family and thousands of friends.
Mr Crean's family said his greatest achievements were as a father to Sarah and Emma and a loving husband to Carole in their 50-year marriage.
Australian Associated Press
