Reko Rennie’s cavernous warehouse studio near Yarra Bend Park is full of old and new work, half-finished ideas and spilled paint.

In one corner there’s a disheveled, taxidermied emu, her head tilted inquisitively. She’s part of a piece Rennie conceived a few years ago and never got around to starting. In the meantime, she’s become a studio mascot. In another corner, there’s a dirt-coated Rolls-Royce. We’ll come back to that.

There are half-finished pieces on the wall alongside a five-year-old graffiti work. Three scrawled symbols repeat across the canvas: an Aboriginal flag, a diamond, and a crown. The diamond is a traditional symbol of the Kamilaroi people in northern New South Wales, where Rennie’s ancestors come from. In Western terms, it’s a lot like a family crest. The crown recalls the trademark motif used by American artist Jean-Michel Basquiat. The work is a reminder of Australia’s original royalty.

Rennie has just finished a piece for Sovereignty, a new exhibition at ACCA focused on contemporary Indigenous art. It’s a five-metre-long banner in neon camouflage emblazoned with gold text that reads “ALWAYS HERE”.

“The whole idea of camouflage is to conceal and hide and blend in,” Rennie says. His version of camouflage could not be more conspicuous. “I want to make camo about not being invisible – proudly declaring who you are and where you’re from.”

It wasn’t that long ago that the symbols of Rennie’s Kamilroi people were outlawed because they were deemed pagan. As late as the 1970s, his people were forbidden to practice their culture and speak their language. His grandmother was forcibly removed from her family at the age of eight. “She was moved around different missions and pastoral stations, and enslaved for 10 years,” Rennie says. “It was systematic genocide, in terms of dislocation, dispossession of culture and identity and family.”

A lot of his work, therefore, is about being loudly and proudly black. He’s making up for lost time. “Aboriginal people today are proud, because it was denied for so long.”

Rennie’s heritage has always been a big part of his work, but he’s always bypassed the traditional “dots and ochre”, which he says is “a romanticised notion of Aboriginal identity”.

“Where I grew up,” – in Melbourne’s western suburbs – “we made graffiti, and worked with bright colours.”

Rennie’s earliest exposure to graffiti was seeing political slogans about feminism and union rights scrawled in white paint around the suburbs in the late ’70s and early ’80s. Then hip-hop culture, graffiti and street art arrived from America.

Graffiti was about rebelling, making a mark, going against the system, he says. But it was also more than that. “What drew me in was creating work in a public environment and having the power to say something.

“Graffiti gave me the tools and medium to express myself,” he says.

He’d discovered the work of Jean-Michel Basquiat, and found a book on Howard Arkley, whose airbrushed paintings of houses and streetscapes put Australian suburbia on the gallery wall.

His dad encouraged him to get a job to support his art practice, so he turned to journalism. Work with the Koori Mail, ABC, SBS and the Age made him articulate and sharp, which fed back into his art. He eventually gathered enough momentum to quit his day job and work as an artist full time.

This warehouse near Fairfield has been his studio for two years. He used to work from home, filling his kitchen with art, spreading out across the bathroom floor and trying not to get paint on the tiles, before rolling into work after an all-nighter. Now, he’s free to experiment and play with different media. This is where the Rolls-Royce comes in.

At first I don’t see that – under a layer of dirt – the 1973 coupé has been hand-painted in the same neon camouflage as some of Rennie’s other pieces. The car is part of his most ambitious project yet – a three-channel film work about an emotional return to country. A few weeks ago he drove the car up to Kamilaroi land in northern New South Wales.

“The car is a reference to when men would have these million-acre properties with maybe a couple of hundred enslaved Aboriginal people, working for rations,” says Rennie. His grandmother was one of them. “Then they’d have Rolls-Royces to take to church on Sunday.” It got him thinking about colonial identity and the role of the automobile. “On one hand there’s this ostentatious wealth, and on the other, misery and abuse.”

He skirted around the area itself. “I won’t set foot on those places,” he says. “There’s too much trauma.”

Now, the car is parked in his studio. Our photographer can’t take pictures of it – it’s under wraps until the full work debuts at the National Gallery of Australia in May.

I run my finger across the bonnet and it comes back thick with the red earth of his ancestral land. There’s a tiny photo of little Reko with his grandmother on the dashboard.

Reko Rennie’s work appears in Sovereignty at ACCA until March 26.

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