The final resting place of Indigenous Australia's first ambassador, Woollarawarre Bennelong, will be preserved after the NSW Government purchased the Sydney property on which it sits.

Key points: Woollarawarre Bennelong travelled to England as Indigenous Australia's first ambassador

Woollarawarre Bennelong travelled to England as Indigenous Australia's first ambassador He died in 1813 and was buried under an orchard belonging to brewer James Squire

He died in 1813 and was buried under an orchard belonging to brewer James Squire The site was identified in 2011 and the property has now been purchased by the Government for about $3 million

Bennelong played a key role in Australia's history as a mediator between Indigenous people and the white settlers of the First Fleet.

He died in January 1813 and environmental scientist Peter Mitchell identified the place where Bennelong is believed to be buried in 2011.

NSW Housing Minister Anthony Roberts revealed on Sunday the Government had purchased that site — 25 Watson Street, Putney, in the city's north-west — for around $3 million.

Historians have established Bennelong was buried near the nature strip of the Putney home. ( ABC News: Jean Kennedy )

He said it was an important step in preserving the culture, history and achievement of "arguably one of our greatest leaders and early ambassadors".

Mr Roberts said the grave had previously been left untended and forgotten.

"It has taken 200 years, unfortunately, for a government and for our community to recognise the contribution of Bennelong," Mr Roberts said.

"It is critical that this site is preserved."

In his role as an intermediary, Bennelong volunteered for a journey to England with his nephew.

Des Madden from the Bennelong Putney Project Committee, which has long been working towards the goal of preserving the burial site, said that decision was incredibly brave given the events of the period.

"The work that he did was incredible," Mr Madden said.

Historian Peter Mitchell in the front yard of the Putney property. ( ABC News: Jean Kennedy )

"He did work towards some type of reconciliation and that story needs to be shared as well. That story continues today."

A committee, which will include Aboriginal community members and Mr Madden's existing group, will be set up to discuss the site's future.

"It's definitely something that's going to be culturally appropriate," he said.

"It's going to be a place where everyone can celebrate the life of Bennelong and also learn more about the story.

"It's a fascinating story."

Mr Madden said Bennelong had many high-profile friends during his life, including brewer James Squire.

Following his death on January 3, 1813, Mr Squire laid him to rest in a contemporary burial site in his orchard.

Mr Madden said the work of scientists had provided a "very accurate" estimation of his location, which at the time was beneath a particular tree and now sits near the nature strip of the Watson Street property.