They said they were setting up the Aboriginal Embassy in protest at the then Liberal government's approach to land rights.

When the sun rose, a police officer asked them how long they intended to stay. One of the men, Billy Craigie said "until we get land rights".

The officer laughed and suggested that would take a long time.

"Well, we'll be here a long time then," Craigie replied.

Fifty years later, the tent embassy (a few days after Australia Day 1972, someone donated a tent to the men) is still outside old Parliament House.

It has become such a permanent fixture that it even features on Google Maps.

In the documentary Still We Rise, filmmaker John Harvey tells the story of the embassy's first year.

"It's a pivotal time when indigenous rights and land rights really got a national and international focus," Harvey said.

"It's actually the longest continuing protest in the world."

Rather than tell the story through modern eyes, Harvey's documentary is made up almost entirely of archival footage from 1972, which lends a feeling of immediacy to the story.

"I really wanted to capture that energy of 1972; they were all very young - early 20s, late teens - when they were setting up the tent embassy," he said.

"As a filmmaker you don't often get to work with archives at this level and the ABC were opening their doors.

"I wanted to take up that opportunity to dive deep into the archive.

"I think one of the things with this film is unfortunately a lot of people who appear in the film have passed away.

"I just thought by making this film from archives we could get their first-hand accounts of what it was like at the time."

Watching Still We Rise, it's hard not to think of similar footage from the United States civil rights movement of the 1960s - images many of us are sadly more familiar with than those of an event happening on our own doorstep.

Harvey said international events like the civil rights fight in the US fed into the movement in Australia.

"It was an interesting time," he said.

"The kind of events internationally at the time, there was the Vietnam War and there was a lot of protests around that with conscription, There was apartheid in South Africa and protests related to that.

"The indigenous movement here was also looking beyond our shores. They were looking at the Black Panthers in the US. You can see it in the film in the material that people are reading, how they're forming their ideas and for self-determination.

"It definitely has that international influence."

Harvey found using the archival footage meant the story wasn't told from his own perspective, looking back to 1972. "That was really important for me," he said.

"The important thing is it's not the voice of one. It's not one person's story, it's many people's story and there are many versions of the story.

"So I really wanted to celebrate the diversity of voices within the film."

The old black and white footage also captures the shock and confusion from white Australia about what was going on.

For many, it would have been the first time they'd heard about the concept of land rights.

And some of them - including journalists - were asking odd questions, like whether they hated white people.

Harvey said as well as anger, many of the protesters had a sense of humour and could joke about such questions.

Also, despite the shock of the protests, Harvey felt many Australians had sympathy for their plight.

"I think whilst that shocked people, it also tapped into that Australian sensibility of the little guy against the powers that be," he said.

"I think a lot of people were able to relate to that."

STILL WE RISE: 8.30pm, Thursday, ABC