Ticking "widow" on forms felt like a cartoon jail door slamming closed on Courtney Johnston's life.

"It was being put into this box that I had no say about. It became really important to me that that tragedy would not be the first thing people thought of when they saw me. That they wouldn't go 'Oh, poor Courtney, the terrible things that have happened to her'."

It was 2012 and Johnston's husband William McAloon had committed suicide, after a long battle with depression.

An art history graduate, Johnston had always planned to become an art curator. But McAloon – who curated art at Te Papa – was older and already established in the job, so to avoid competing she'd switched focus. She'd worked as a visitor host at Te Papa and as publicist at City Gallery, created digital connections for the National Library and was by then running a digital media company.

But after McAloon's death she saw the vacancy for director of Lower Hutt's Dowse Art Museum and Petone Settlers Museum. Out of sheer cussedness, she applied. The arts world was such a closed shop – one gallery director left, then everyone played musical chairs. It pissed her off.

She was the underdog of five candidates – the other four had all done similar jobs before. But in her world of loss, anything was possible.

"Grief can shut you down, but sometimes if you're really lucky it breaks you open. I felt really raw and open to the world, but I also felt like I had nothing to lose."

It's fitting that Te Papa founding chief executive Cheryll Sotheran was on the selection panel, because winning that job launched Johnston on to the path to this office. The office (already festooned with her step-daughter's unicorn drawings) of the youngest chief executive of one of the country's biggest – and most controversial – cultural institutions.

MATTHEW TSO/STUFF Before joining Te Papa's leadership team in 2018, Johnston ran Lower Hutt's Dowse Art Museum.

Having been on Te Papa's leadership team for just a year, as director of audience and insight, 40-year-old Johnston was seen as a long-shot choice.

When she started at the Dowse, she said a measure of her success would be the happiness and fulfilment of her staff. That's no doubt one of the reasons Te Papa chairwoman Fran Wilde chose her ahead of more experienced competition, to lead the museum out of a year of pain, anger and bad press.

Petite and quietly spoken, Johnston's a warm breeze drifting through the exhibition halls, stopping for chats with museum hosts, greeting them by name.

But she will have the job of a lifetime restoring morale, which hit rock bottom last year following a restructure that ruptured relationships inside and outside the museum. Staff called the environment toxic; there was an exodus of senior people; and scientists around the world spoke out against the axing of collection managers who were internationally renowned in their fields.

Johnston won't say the restructure was a mistake, or that she would have done things differently. But she acknowledges it's left sores that need healing.

"I think working at Te Papa should be the pinnacle of a New Zealand museum professional's career ... The last few years, with the restructures, have been hard on people. I take that responsibility really deeply."

The staff satisfaction survey already shows improvement, and Johnston says she will ensure she's available to staff and she is trying to repair external relationships. Former Te Papa collaborators turned trenchant critics – moa specialist Trevor Worthy and giant squid expert Steve O'Shea – say they have not been approached.

GRAHAM SPENCE/TE PAPA The axing of world-class mollusc expert Bruce Marshall sparked outrage in the science world.

Following a string of short-lived chief executives, Johnston plans to stick around for 10 years. And as a museum person, she reverses a trend to hire business bosses, which angered the museum sector. While she comes from the art world, she says she's equally committed to the three pillars of Te Papa: Papatūānuku (Mother Earth); Tangata whenua (Māori); Tangata Tiriti (non-Māori).

"You can't be part of our environment and care for our environment without science. You can't be a New Zealander without understanding Māori culture and the Treaty relationship. You can't understand human imagination and what potential we have to communicate with each other without art. You can't think about our past and think yourself into our future without understanding our history and having access to it. That's the magic of museums."

Four years on the board of Museums Aotearoa, including 18 months as chairwoman, also gave her a good insight into the wider museum context. However, she acknowledges science is her weak point.

"Science is the area where I've got the least hands-on experience, so it's the place where I do want to commit the most to spending time."

Growing up, Johnston's world was a single Taranaki street. Mangorei Rd housed the family dairy farm settled by her great-grandparents when they emigrated from Scotland. It hosted her primary school and the secondary school where she met the first female mentor who redirected her life's compass.

Her family wasn't arty, but her form teacher Claire Hall also taught art history and her 7th formers seemed the height of glamour. And when Johnston got a car, she discovered New Plymouth's Govett-Brewster art gallery.

"Art for me has always been a window into the way that other people think, the way that other cultures think. It can transport you through history, and through perspectives."

She was inspired by the energy of young Kiwi artists such as Michael Parekowhai and Shane Cotton, who were examining what being a Kiwi meant through art.

Twenty years on, Te Papa – like cultural institutions worldwide – is having that same discussion about museums. The International Council of Museums has even proposed changing its 50-year-old definition of a museum, to include potentially politicising concepts such as "contributing to human dignity and social justice, global equality and planetary wellbeing".

SUPPLIED/TE PAPA Farmers hit out at Te Papa over its use of a fake sample of farm stream water in a water pollution exhibit. Johnston says she will not shy away from difficult issues.

Johnston says Te Papa is already ahead of the game, having been set up as a forum for the nation. She wants Te Papa to get Kiwis talking. And despite farmers getting upset at Te Papa using brown water to illustrate farming pollution, she has no plans to back away from difficult discussions.

"We can't afford to shy away from hard stuff, just because it's uncomfortable to talk about. Because the hard stuff is the most important stuff for us."

However, she acknowledges that museums come with historical bias. A recent collections review found Te Papa's story of New Zealand was skewed male, white and middle to upper class.

"We can see the imbalance of the past and work to address it," Johnston says. "I think it's one of the most powerful areas we get to act in."

ROBERT KITCHIN/STUFF Johnston calls herself a feminist and hopes to redress the museum's historical biases, including under-representation of female artists.

At the Dowse, Johnston focused on Māori and female artists, turning up the volume on little-heard stories and dialling down those that have had more airtime.

Johnston says she has not yet considered whether objects with no obvious New Zealand connection, such as the museum's Egyptian mummy and international art collection, should stay or go.

Having now completed its Toi Art and Te Taiao nature exhibition renewals, the next focus is the natural history, Pasifika and mana whenua galleries. Johnston plans to use that work to improve diversity, and to work with Māori to ensure their taonga get the best treatment at Te Papa, or to support them to show their treasures in their own spaces.

"It's how do we amplify all those different voices that make New Zealand up, but in a way that doesn't divide."

Cameron Burnell While at the Dowse, Courtney Johnston organised a feminist Wikipedia edit-a-thon to create profiles for female Kiwi artists such as jeweller Lisa Walker.

Johnston started her art history studies in Dunedin, but moved to Victoria University to be closer to her Dad, who was in rehab for a year after a motorbike accident left him with such serious brain injuries he did not recognise his family.

There she studied under former National Art Gallery director Jenny Harper, one of several female leaders she counts as role models. Others include former National Library boss and "rambunctious, enthusiastic visionary" Penny Carnaby and Sotheran.

Johnston calls herself a feminist and remains frustrated at the relative neglect of female artists and the low numbers of women working as museum directors. While at the Dowse, she ran a Wikipedia edit-a-thon to add more female artists to the online encyclopaedia.

In her early 20s, Johnston had a theory that she wasn't offered art curator jobs because she dressed wrongly – she didn't look sophisticated enough or wear that weird World bustle skirt all the curators were wearing. She's kind of joking, but also kind of not. During the Te Papa interview period she bought her first suit.

"It is all part of being a female leader: people notice your clothes."

Prejudices endure – when she was general manager of Boost New Media and walked into meetings with the company's tall, confident founder, people assumed this small lady by his side was the note-taker. And when she talked to a recruiter about her life goals, he said there were two barriers in her way – one, that she presented young, and two, that she was a woman.

"Let's just politely say I was like, bugger you, I am going to show you."

ROSA WOODS/STUFF Te Papa critics will be hoping Johnston will bring an era of stability to the national museum.

Coming as she does from a digital media background, traditionalists will be nervous Johnston will prioritise whizzy technology over the collection objects.

Both is best, she says. "I'm a digitally inclined person who still really loves things". She collects New Zealand art and ceramics. The wedding rings for her marriage to McAloon were made by jeweller Kobi Bosshard. When McAloon died, she gave them back, and Bosshard merged them to create a pendant.

And it was a Bosshard ring that Johnston chose to mark her Te Papa CEO appointment – continuing a tradition of marking big life moments by buying art.

It's been a huge 18 months for the driven achiever. She no longer has to tick the "widow" box on forms, having married Pātaka Gallery director Reuben Friend, and acquired an instant family of three step-children, aged 9, 10 and 11. It's been an exercise in patience, self-effacement and growing up, but also delightful, Johnston says.

She's also earned a brown belt in Brazilian jiu-jitsu, a sport she describes as aggressive cuddling. She'd always wanted to try a martial art but hated raising her voice, so she chose the non-yelling, non-chopping variety. She trains every Monday, Wednesday and Saturday and it's been her refuge since McAloon died.

"It was just so relaxing being in a place where no-one knew me and where I could only think about what I was doing with my body."

Cameron Burnell/Fairfax NZ Johnston no longer ticks the "widow" box, having married Pātaka director Reuben Friend.

Years ago, Johnston did one of those human resources tests, which summed her up in two words – responsibility and adventure. In the bird world, she's mostly eagle, with a bit of peacock.

Leadership is her happy place – she figures everyone has a natural stress level so you might as well fill it with the best, gnarliest stuff. There will be no shortage of that running the Museum of New Zealand.

Former Hutt City Council boss Matt Reid was also on the original Dowse selection panel. He says it was Johnston's attitude and world of difference that prompted him and Sotheran to take a punt on her. Sotheran built an experience that led the museum world. He expects Johnston to take it to the next level.

"I hope she does great things, and I will be holding her to account if she doesn't."

Him and the rest of New Zealand.