Guardian Australia has won the digital history prize in the New South Wales premier’s history awards for its Indigenous massacres project, The Killing Times.

The collaborative series with the University of Newcastle’s colonial massacres research team found there were at least 270 frontier massacres over 140 years as part of a state-sanctioned and organised attempt to eradicate Aboriginal people.

The Killing Times documented the history of Australia’s frontier wars through the development of an interactive map showing every verifiable site of frontier conflict in the process of colonisation, from 1788 to 1930.

To create the map, Guardian Australia’s team refined, extended and analysed the University of Newcastle’s dataset and, using the same strict research methods, identified an additional 15 sites in Western Australia, and published the first full picture of the continent’s Indigenous massacres.

The map is the first of its kind to be produced by any media outlet, and uniquely can be searched by date, time, location, postcode, perpetrator group and/or death count.

Judges of the history awards said: “The Killing Times makes a profoundly important contribution to history and public debate in Australia.

“It harnesses the capacity of interactive technology to open up the contested political space of the ‘history wars’ and shows the power of technology to sweep aside national myths to reveal a violent and quotidian world of fatal clashes between Indigenous Australians and settlers.

“By pairing contemporary sources with cutting edge technology, the creators of The Killing Times have produced a resource that challenges, provokes and demands more from Australians.”

Guardian Australia’s Indigenous affairs editor, Lorena Allam, led the project, with its data editor, Nick Evershed, developer Andy Ball, the reporter Paul Daley, the photo editor, Carly Earl, and interns Ciaran O’Mahoney and Jeremy Nadal contributing.

After the awards Allam said: “This prize highlights the role of the media in telling the truth about our nation’s history.”

The Australian history prize was awarded to Meredith Lake for The Bible: A Cultural History. The general history prize went to Christina Thompson for Sea People: The Puzzle of Polynesia. Jon Rhodes won the NSW community and regional history prize for Cage of Ghosts, and the young people’s prize went to Alison Lloyd and Terry Denton for The Upside-down History of Down Under.

• On 2 September 2019 this article was amended. A previous version gave the wrong winner for the NSW community and regional history prize.