Indigenous graduate John Morseu holds history in his hands at National Library

But when John Morseu first laid eyes on a photo album dating back to the 1920s and 30s, it wasn't just the goats and lambs roaming unsealed roads that caught his attention. It was how closely the landscape matched the one in his imagination.

Growing up on Thursday Island in the Torres Strait, he was used to hearing stories about the old times. Like many Indigenous cultures, it's how his people communicated memories, and how they continue to keep their culture alive today. But seeing actual photographs of the island before bitumen was a revelation.

"We're a very strong oral culture, so to see the pictures just kind of backs up oral tradition," he says.

"It's not that I questioned oral history – I didn't know how to visualise it, and you only have your own way of visualising it. So when you see it, it wasn't too far off what they said."

Morseu is the current Indigenous graduate working at the National Library of Australia, and has had several lightbulb moments while mining the library's surprisingly large collection of materials from the Torres Strait.

Although his family lived on Thursday Island, his is the first generation to be raised and educated on mainland Australia. But he often returns to his home town, and has never let go of his cultural identity. It's a trait shared by many Torres Strait Islanders, and he's already created a research guide for people who, like him, are keen to know more about their history.

He says the guide records cultural and social history in ways that can have a dramatic effect on individuals or communities from the Torres Strait, be it fragmented – like the photo albums he helped the library to acquire – or comprehensive research materials, like the journals of the British explorer Alfred Cort Haddon.

Haddon was the first anthropologist to work in the strait, and was there to document the local society's shift from a head-hunting culture to a profoundly Christian one.

"He was the one who came and recorded the islands when we were influenced by Christianity, so he was capturing that period before we lost our … head-hunting culture,"Morseu says.

"We don't have a concept of time, so it was 'before time' stuff."

He says unlike some Aboriginal Australian cultures, communities in the Torres Strait have thoroughly embraced early Western influences.

"We live in both – we have a very strong Christian belief, but we also counteract that, I guess, with our traditional beliefs," he says.

"And then we're only just starting to deconstruct the differences, or what's been transferred.

"Christianity was a very positive thing, because we were fighting with each other – different islands, different clans. When Christianity came, it made us unite, it made us come together, be more peaceful and kind of move forward. I guess that was the missionaries' ideal thing too, but for us, I think it was a positive thing."

Reading Haddon's diaries, Morseu understood, on a deeper level, why Haddon took so many items back to Cambridge in England with him, and more of the stories from his childhood were filled in.

But nothing has compared to seeing the album of photographs and cache of letters that form part of the Mosby collection. Morseu is descended from the Mosby clan, and, among the images of native islanders, white missionaries, local priests, children and animals, he has been able to recognise roads, and, more importantly, put names to some of the otherwise unidentified Indigenous faces.

The handwritten letters in the collection were exchanged between Elma Mosby, his ancestor, and Edith Wyly, the daughter of a missionary and the niece of Reverend Samuel MacFarlane, one of the main evangelists who arrived in the Torres Strait the 1870s.

"The album has all the missions, where the missionaries went, but it also shows our first two ordained priests," Morseu says. "[They were] native islanders who were the two first priests, and it just shows life in those early 1900s, which is very different to what we have today."

The guide he has designed also marks Thursday Island out as a former township that was once one of Australia's most valuable towns, at the peak of the pearling industry. It's a way of reaching out, not only to natives of Thursday Island who have moved away, but to those many international residents, from Japan or China, for example, who have lived there over the years.

"I don't forget, but people forget, that Canberra's so far away from everywhere, and it's definitely very far away from the Torres Strait, and Torres Strait hubs – Townsville, Cairns, Mackay, where there's very big Torres Strait communities," he says. Highlighting the many unpublished resources in the library's collection has already helped him identify more materials, and put more people back in touch with their own culture.

And it's a movement that is already gaining traction. Someone on Thursday Island has already set up a Facebook page, to share stories about the history of the island.

"For me, it's just the work here that the library had perpetuated, this social movement to start thinking about where we've come from," he says.

"Particularly islanders like me, I'm the first generation to live on the mainland, but there are other families who've come down in the war, so some of them are second, third or even fourth generation.

"It just makes those descendants start thinking about who they are and where they've come from. It's really interesting, family stories. I know I have family stories about the war."

One of the most striking things he has noticed about his work is that, unlike many young Australians from other cultures, his has a very entrenched identity and knowledge of its own history.

"It's interesting because as Thursday Islanders, or as Torres Strait Islanders, we already know the stories of each other," he says.

"Especially my generation. I know everything about my generation, my parents; and then my parents would know about their parents, so it's nothing that we don't know, it's just about sharing it again and regurgitating it again so young people understand."

You can use John Morseu's research guide via the National Library's website, at nla.gov.au.