The master of ceremonies, former Labor minister Craig "Emmo" Emerson, probably summed it up best while listing the dignitaries in attendance.

"Albo, ScoMo, Emmo — a very Australian celebration," he told a packed Sydney Opera House.

"And, this is a celebration."

Thousands of people gathered inside the harbourside icon and at its forecourt to pay tribute to former prime minister Bob Hawke, who died aged 89 on May 16.

Among them were Mr Hawke's widow Blanche d'Alpuget, his family, and a slew of politicians, diplomats and dignitaries.

The Opera House was a fitting place to farewell Mr Hawke, who launched his first campaign there in 1983.

He would go on to win four elections.

Blanche d'Alpuget said her late husband's death had sparked a "national outpouring of grief". ( ABC News: Brendan Esposito )

There were five former prime ministers in attendance, including Tony Abbott, who was last month criticised for claiming Mr Hawke had a "Liberal head" the day after his death.

Paul Keating, Mr Hawke's former long-time treasurer who rolled him for the nation's top job after a 1991 leadership challenge, spoke at the service.

The pair's relationship broke down after Mr Hawke was dumped but they reconciled last year and had begun to meet regularly.

Paul Keating reflected on his personal relationship with Hawke. ( ABC News: Brendan Esposito )

"Bob and I would have private skirmishes over this policy or that, even criticise one another to immediate staff," Mr Keating said.

"But by instinct and a very large dollop of friendship, we always remained wedded to the same objective, a point even the closest of our staff sometimes fail to comprehend.

"I'm not sure they knew how stuck together we were."

Ms d'Alpuget said her late husband's death had sparked a "national outpouring of grief".

"With today's transformative service, we smile again, we glow with pride for the presence among us for almost 90 years of a great human being," she said.

'His moral compass did not waver'

Prime Minister Scott Morrison, the first speaker at the service, said the 1980s in Australia would always be "the Hawke era".

"Our 23rd prime minister was a proud and faithful son of the Labor movement," he said.

Prime Minister Scott Morrison makes a point during his tribute. ( AAP: Dean Lewins )

"He became one of the proud fathers of our modern Australia."

Former Labor leader Kim Beazley, the Governor of Western Australia, delivered the eulogy and asked: "Was he our greatest prime minister, or our greatest Labor prime minister?"

"Bob told me he was neither.

Kim Beazley provided a moment of humour during the service. ( ABC News: Brendan Esposito )

"His aspiration was to be our greatest peacetime prime minister."

The loudest applause was saved for the Sydney Symphony Orchestra and Sydney Philharmonia Choir's rendition of the Hallelujah Chorus.

Mr Hawke had conducted Handel's famous oratorio at the same venue 10 years ago for his 80th birthday, and a video of that moment was beamed over the stage.

He was remembered as a larrikin with an unwavering commitment to his job.

Actor Jack Thompson arrives at the Opera House ahead of the service. ( ABC News: Brendan Esposito )

Federal Labor leader Anthony Albanese said Mr Hawke was "no shrinking violet", and a man who wanted to protect Australia from "those who sought to divide us".

"Yet when he was up against those forces of division, his moral compass did not waiver," Mr Albanese said.

"Beneath that cloud of hair, the sunshine would give way to lightning and to thunder.

"But the sunshine always returned and his positivity changed the nation for the better."

Look back at how the memorial service unfolded.