Invercargill has bid farewell to the "absolutely extraordinary" late Sir Tim Shadbolt in a service marked by humour and reflection, but a stinging rebuke of his final term in office.

Hundreds of friends, family, community members and political leaders gathered at the Civic Theatre for the public funeral on Friday afternoon, while thousands of others watched on an online livestream.

Tributes at the service moved between Sir Tim's capacity for mischief to his powerful advocacy and leadership, tracing Sir Tim's life from activism to public office, as the Waitematā and Invercargill mayor.

However, partner Asha Dutt said she could not speak without raising an "truly awful" time in Sir Tim's life - which was his final term as Mayor of Invercargill.

The Invercargill City Council of 2019 should be ashamed of how Sir Tim exited his career, she said.

"I made the promise to Tim that I'd raise these points," she said.

During that term, Sir Tim walked into the council chambers each day with no friends, she said.

"Let me clearly state, it wasn't Tim who ailed and wasn't capable of doing his job. It was the extreme stresses that were placed upon him by people that should have supported him, that turned his health, and turned my own," she said.

"The council of 2019 have blood on their hands. That's the shot I want to fire, Tim would be proud."

She said she was staggered by the number of people who had come forward with "Tim stories" following his death - who had been touched or moved by him.

"He was receptive to everyone. He gave everyone the time of day," she said.

"He was a unique person at a time when the world needs more unique people to propel themselves from the mould."

Sister Tui Shadbolt recalled Sir Tim's ability to communicate, lift spirits and mobilise people.

He devoted himself to making communities stronger with warmth, wit and humanity, she said.

"He spent his life fighting the apathy. He just wanted people to vote," she said.

"He was always, always happy to serve."

Son Robert Shadbolt recalled his father's relentless honesty, work ethic, and can-do attitude.

"Dad - he was an ideas man, and planning was never something to slow him down," he said.

"We miss you - your empathy, humour, warmth - and we come together today to celebrate someone who really, really lived."

Family friend Sue Roswell described an "amazing friendship, through many life changes" with Tim, while lifelong friends, "Tim's Team" - consisting of John Bower, Margaret Evans, Doug Owen and John Bower, paid tribute to a "truth-seeker" and "change maker".

A haka performed by Mana Tuakiri Photo: Katie Todd/RNZ

"I'm actually a little bit envious that we don't have more people around like Tim that can inspire and get people moving. Invercargill is a model for the rest of New Zealand," Owen said.

"He had this immense ability to put the spotlight on stuff that was really important to New Zealanders...he was an aggressive reformer, but it was filled with love," Evans said.

"May the name of Tim Shadbolt stay forever."

Sir Tim first came into the national spotlight as a student activist in the 1960s, drawing attention to issues including apartheid and the Vietnam War.

Māori activist and artist Tame Iti recalled working with Sir Tim at the Bastion Point occupation in 1977.

Sir Tim was proof that "even the establishment surrenders if you shout at it enthusiastically for a long time", he said.

"Tim did not just attend protests. He was the protest," he said.

Māori artist and activist Tame Iti speaking at Sir Tim Shadbolt's funeral. Photo: Katie Todd

Long-time friend Pita Turei recalled uniting with Sir Tim over a shared belief in the working man.

Both came from violent and rugged homes, and neither grew up with their fathers, he said.

They talked about the idea of revolution, he said.

"We were going to change the world - he did."

During his time as Invercargill's leader, Sir Tim championed the Zero Fees scheme at the Southland Institute of Technology, in a bid to attract more to the south and keep more young people in the region.

Major buildings including Stadium Southland were built during his term, and others including the Civic Theatre were refurbished.

Invercargill MP Penny Simmonds described Sir Tim as "unconventional, unexpected...hilarious and deeply loved."

An "immense" capacity for compassion underscored his leadership, and his decision to advocate for zero-fees was part because he saw an economic opportunity, but also because he saw its power to open tertiary education to those long-excluded, she said.

"Today...we mourn the loss of an absolutely extraordinary man," she said.

The spirit of Sir Tim will live through his community for a long time, son Ben Shadbolt said.

"I'll always feel so much love for this bugger," he said.

Pastor Graeme Pope thanked mourners who had come from near and far.

He described Sir Tim as humble and generous with his time, attention and love.

Attention was often put on what Sir Tim achieved, but what truly mattered was who he was, he said.

Sir Tim was made a Knight Companion of New Zealand Order of Merit in the 2019 New Year's Honours List for his services to local government and the community.

Sir Tim's cortège heading through the main streets of Invercargill. Photo: Katie Todd/RNZ

He died on 8 January, aged 78.

The funeral was followed by a cortege through the city out to Invercargill Airport's Sir Tim Shadbolt Terminal, and to Eastern Cemetery for a private interment.

The Invercargill City Council has been approached for comment.

Katie Todd, Otago/Southland reporter

Published by permission