Duke Regan is only four, but he knows every single word of the Acknowledgment of Country.

He learnt the words at kindergarten: "I'd like to acknowledge the Gadigal People of the Eora Nation who are the traditional custodians of the land..."

His kindy, in Sydney's Northern Beaches, joins thousands of other forums around Australia that use these words to pay respect to Indigenous elders past, present and emerging.

Duke prepares to acknowledge country at his family's Jewish Passover celebration. ( Supplied: Jacqui Parker )

The Acknowledgement of Country is used in parliament, at sporting events, in museums and on the news.

This is how ancient traditions became a core national custom in little over 20 years.

The origins

The Acknowledgment of Country is firmly entwined with another ritual — the Welcome to Country.

Unlike the acknowledgment, which can be given by anyone, the welcome is always given by an Aboriginal person, a traditional custodian, with ancestral ties to the land upon which an engagement takes place.

The origins of the Acknowledgment of Country lie with another ritual, the Welcome to Country. ( ABC Goldfields: Tom Joyner )

The welcome has been a core part of the diplomacy systems that have existed between Indigenous nations for millennia.

"We see the Acknowledgment of Country as being more contemporary in its origin, certainly the way that we engage with it now," says Yorta Yorta and Dja Dja Wurrung man Tiriki Onus, who runs the Wilin Centre for Indigenous Arts and Cultural Development at the University of Melbourne.

"[But] that practice of acknowledging your place, of being able to speak as a visitor, is something that has existed for thousands of generations."

From 1788, when the British colonised the land that would become Australia, welcomes and acknowledgments took on a new political form, but they were far from customary.

One noteworthy welcome came in 1978 when Richard Walley and Ernie Dingo, then part of the Middar Aboriginal theatre company, were asked by a group of Polynesian performers to give them a Welcome to Country.

It was a powerful performance and in the years that followed, Walley was asked to give similar welcomes at a travel show in Perth and a Miss Universe Pageant.

But despite this, Mr Onus remembers the tradition as being primarily associated with Indigenous political movements.

"This act of acknowledging country wasn't something that was terribly prevalent in my childhood in the 80s," he says.

"It was always a very profound act in a political activist sense to acknowledge the unwritten history of a place as a way of asserting the sovereignty of a place."

Tiriki Onus remembers the Welcome to Country as being primarily associated with Indigenous political movements. ( ABC News: Meghna Bali )

In the 1990s, which the Keating government coined "the reconciliation decade", the welcome found a new purpose within the institutions being set up to advance Indigenous-state relations in Australia.

Through one of these bodies, the acknowledgment was also formalised.

Yawuru man Pat Dodson, now a Labor senator, became the chair of the Council for Aboriginal Reconciliation, which was crucial in bringing the acknowledgment to prominence.

Patrick Dodson when he was chair of the Council for Aboriginal Reconciliation. ( Getty: Matthew Fearn/ PA Images )

"Since settlement and prior to native title determinations, Welcome to Country tended to be more generic — acknowledging wider groups like Koori, Murri or Noongar," Senator Dodson says.

"For non-Indigenous people, Welcome to Country is a way to respect those descendants who survived colonisation, extermination and settlement, acknowledging continuing relationships to particular tracts of land.

"The work of the Council for Aboriginal Reconciliation (CAR) encouraged strangers to recognise country, then, as people got stronger, the welcome developed."

'A very organic movement'

By the late 90s Australia's attitudes towards its past had been thoroughly challenged by the famous Mabo decision and the native title legislation created in its wake.

"The colonial rhetoric of terra nullius — 'land belonging to no-one' — long dismissed Aboriginal and Torres Strait Islander connections to country," says Bundjalung woman Karen Mundine, the chief executive of Reconciliation Australia, the organisational successor to the CAR.

"Until the movement and historic Mabo decision, the rhetoric of terra nullius was problematically used as an attempt to 'justify' unjust colonial policies and practices."

Mr Onus remembers that during the months after Mabo, the Acknowledgment of Country started to flourish amongst "grassroots communities concerned with issues of reconciliation".

"For me it started as a very definite political act but now in a contemporary sense it has morphed into something that is much more shared," he says.

According to federal politician and Wiradjuri woman Linda Burney, who was a member of the CAR when the acknowledgment was formalised, its growth was organic.

"It wasn't strategised or planned," she says.

"Once it got out to civic life it was something that people saw as an important way to tell the truth of the Australian story.

"Some years down the track it became a very formal part of Australian life, being done at gatherings of big corporations, union gatherings, religious ceremonies, and all parliaments across Australia."

A genuine genuflection?

The Acknowledgment of Country has faced some criticism and resistance from parts of Australian society.

Recently the WA branch of the RSL decided to ban acknowledgments and welcomes at Anzac Day services. A swift public backlash ensued, and the decision was overturned days later.

In 2010, then prime minister Tony Abbott also criticised the acknowledgment, which he described as "'genuflection to political correctness".

Some in the Indigenous community have echoed that sentiment, raising concern that the repetition of the acknowledgment has caused it to lose meaning.

But for Ms Burney the power of the acknowledgment has well and truly lived up to its founding purpose as a vehicle for reconciliation.

"If you're an Aboriginal person sitting in the audience during an acknowledgment it says something very loudly — that you are respected and recognised," she says.

"It's also very educative as well.

"We've got a country that's more aware of Aboriginal Australia than ever before, and we've got a more of a notion of its ancient history."

Linda Burney says the acknowledgment of country tells Indigenous people they are "respected and recognised" ( ABC News: Rhiannon Shine )

Reconciliation Australia's latest barometer shows that 90 per cent of Australians feel the relationship between Aboriginal and Torres Strait Islander peoples and the wider Australian community is important.

"As all sections of Australian society have become more aware of the history and cultures of Aboriginal and Torres Strait Islander peoples and communities, so too has people's desire to show respect," Ms Mundine says.

"Welcomes and Acknowledgements of Country are a good starting point to engaging on issues of reconciliation and understand of Aboriginal and Torres Strait Islander culture."

Mr Onus has found the acknowledgment to be a powerful tool in "helping us to reconcile some of the more unsavoury parts of our shared history".

He believes the impacts of the Acknowledgement of Country are yet to be fully realised.

"The act of acknowledging country and seeing oneself as part of the stories of the place can contribute a lot the society we build going forward," he says.

Tiriki Onus believes the impacts of the Acknowledgement of Country are yet to be fully realised. ( ABC News: James Carmody )

When Duke Regan gives his acknowledgment, "custodians of the land" sounds more like "custard with dad".

The true meaning of the words are still a few years off.

But at some stage it will make sense to him, as it will to thousands of other kids.

"Kids haven't known a world without an acknowledgment … and that makes me a bit excited for what it may become in the future," Mr Onus says.

"The act of acknowledging country and seeing oneself as part of the stories of the place can contribute a lot the society we build going forward."

Walking Together is taking a look at our nation's reconciliation journey, where we've been and asks the question — where do we go next?

Join us as we listen, learn and share stories from across the country, that unpack the truth telling of our history and embrace the rich culture and language of Australia's First People.