Marlon Williams recalls a survey he once read about how often people think about death: on average, once a week. He laughs incredulously. “You know that statistic about men thinking about sex once every seven seconds? That’s how often I think about death.”

In an interview promoting his fourth solo studio album, Te Whare Tīwekaweka, this existential conversation is unexpected. But increasingly, the Aotearoa/New Zealand artist is noticing the way his career pulls him further and further from his roots, and his wellbeing.

Often, his thoughts are concerned with admin – with death cleaning and the worry of not having his affairs in order. But there’s also the niggle of a life not fully lived – something he puts down partly to the touring lifestyle.

“There’s a feeling of impermanence. You make a lot of noise in a lot of places, but you’re not boring that one hole,” he says.

Last time Williams spoke to Guardian Australia, in 2022, he was releasing My Boy: a “Māori disco bop” album featuring Māori instrumentation and strumming techniques, and a smattering of te reo (Māori language). Now he’s gone deeper, creating an album entirely in his ancestral language. Te Whare Tīwekaweka reverberates with a longing for connection before the opportunity is lost – something he seems to feel in his life, and in his relationship with te reo. There’s a Māori saying: it takes one generation to forget language and three to get it back.

Williams is of Ngāi Tahu and Ngāi Tai descent, with his mother’s tribe from the South Island and his father’s from the North Island. He went to a total immersion preschool where children speak only te reo, but the language was lost when he entered primary school.

“There’s shame in not knowing the language already, and pain in my own family of not knowing it,” he says. Over the past few years he started taking the odd class, but also teaching himself.

Committing to an album entirely in his ancestral tongue filled him with “whakamā (self-doubt)”, he admits: “I’ve been psyching up for a long time, just finding the gall.” The album’s title translates as “The Messy House” – his acknowledgment that the grammar and phrasing may not be perfect.

Te Whare Tīwekaweka is released at a tumultuous time for te reo and race relations in Aotearoa. Since being sworn in, in November 2023, the rightwing coalition government has moved to wind back the use of te reo Māori within its departments. In November 2024 it introduced legislation to reinterpret the Treaty of Waitangi, which upholds Māori rights.

“There might be a referendum, which, as we know from Australia, can lead to pretty terrible things,” Williams says.

I meet Williams in Melbourne, where he used to live, the morning after a long day of commitments. Hunched over a 10am bowl of pho, he admits to usually rising at 3pm, being a night owl. Kicking his brain into gear is made harder by the care with which he feels he must broach the subject of language – particularly at this moment in Aotearoa/New Zealand politics.

“I considered not venturing into it at all, because it’s so politically loaded,” he says, adding that the timing of the album itself is coincidental: “It has been in the works for a long time and is a very personal project.”

Williams seems caught between a rock and a hard place. He’s second-guessing his credentials as an unwitting poster boy for te reo, but also the public appetite for an album in language. When he tells people about the album, he notices his tone shift depending on who he’s talking to. Sometimes he sounds apologetic – “but it’s all in Māori”.

This angst is striking given the amount of praise and acclaim he’s enjoyed in his career so far. He’s won numerous Apra and Aotearoa music awards, and previous albums have reached No 1 in Aotearoa/New Zealand and the top 10 in Australia. In May, he will play Sydney Opera House as part of Vivid Live, followed by shows in New York, Los Angeles and London, before returning to Australia for Melbourne’s Rising festival. A documentary covering the making of his latest album, Marlon Williams: Ngā Ao E Rua – Two Worlds, opens in New Zealand in May before hitting Australian cinemas.

In recent years, Williams has been working on setting up a more balanced life, but it’s still a work in progress. Step one: moving home. He had relocated to Melbourne in 2013 for a more immersive musical life, living for a while at the Yarra Hotel in Abbotsford, during which time he and his friends formed the Yarra Benders – the band that still tours and records with him.

During the pandemic he moved back to Lyttelton, a small port town on the South Island of Aotearoa/New Zealand, in an attempt to replant his roots. “It’s stunning. I’ve been going out kayaking and gathering mussels, cooking them up,” he says.

He’s been hanging out with Kommi, a non-binary solo artist who lectures in Māori and Indigenous studies, and who tweaked Williams’ “pigeon Māori” lyrics. Williams had grown up seeing Kommi present on Māori music TV. When they started running into each other at parties, they hit it off.

Among the album’s other collaborations is a duet with Lorde, on the track Kāhore He Manu E. The singer had been doing her own studies of te reo.

“Her pronunciation is beautiful,” Williams says. “She’s such a sound-oriented person that she can hear a vowel sound that’s imperceptible to most people.”

Another track, Korero Māori, features a kapa haka choir (which will also feature in his bigger live shows) and takes a woman’s perspective.

“It translates as ‘Speak Māori’, but it also means ‘plain’, so it’s like, ‘don’t bullshit me’,” Williams says. “It’s talking to a man who’s world-weary. There are lines like, ‘I’ve seen a map of the world, don’t try and use big words on me. I’ve seen a map of the world, and I see you here before me. You left a Māori and you came back a Māori.’”

There it is again: that theme of being away too long. It’s also visible in the video for Aua Atu Rā, in which Williams lies on a Māori therapist’s couch. He’s dressed in a suit and tie – the same outfit a figure wears on the album cover art. It’s an old drawing his mother did, depicting a lean, tall man trudging wearily through the night towards a house.

“I knew that drawing as a child, but I’d forgotten,” he says. “I saw it again a few years ago. I said to Mum, ‘Oh, that’s me.’ She said, ‘No, I painted that when I was pregnant with you.’”

And now Williams must pull on his proverbial suit once more and leave, initially for a tour of the US. He will be shadowed by his fear of missing out on “the things that you’re supposed to experience” back home in his community.

Most would expect a young musician to be revelling in this moment. “I know,” he says. “It’s like I’m having an inverted midlife crisis.”

• Te Whare Tīwekaweka is out on 4 April. Marlon Williams is playing at Sydney Opera House on 29 May as part of Vivid Live and at Melbourne town hall on 4-5 June as part of the Rising festival.