In June 1838, white settlers were expanding into the New England region of the Colony of New South Wales, on the traditional lands of the Kamilaroi people near the Gwydir River, leading to conflict over land and resources between colonists and Aboriginal people. A group of about thirty-five Wirrayaraay people, part of the Kamilaroi, had been invited to camp near Henry Dangar's Myall Creek station by convict stockman Charles Kilmeister for protection from marauding stockmen operating in the district.
On 10 June 1838, John Henry Fleming, a free settler, led a group of eleven stockmen — mostly former or assigned convicts — to the station. The Wirrayaraay fled to a hut seeking protection, but the stockmen tied them together with rope and led them away to a gully about 800 metres from the station huts, where they killed all but one woman, whom they took captive. Station hutkeeper George Anderson, who refused to take part, said he heard only two shots; testimony at trial indicated most victims were killed with swords, and that children had been beheaded. The party later returned, dismembered and burned the bodies, and searched for other Wirrayaraay people who had been away at a neighbouring station.
Station manager William Hobbs discovered the remains days later and reported them, and squatter Frederick Foot carried the report to Governor George Gipps in Sydney. Gipps, supported by Attorney General John Plunkett, ordered Police Magistrate Edward Denny Day to investigate. Day arrested eleven of the twelve accused; only Fleming evaded capture.
Two trials followed before the Supreme Court in Sydney. In the first trial (R v Kilmeister No. 1), heard from 15 November 1838, all eleven accused were acquitted after a twenty-minute jury deliberation, despite testimony from Anderson, Hobbs and Day. A second trial (R v Kilmeister No. 2) proceeded against seven of the men on a separate charge concerning the killing of an unnamed six-year-old Aboriginal child. On 30 November 1838, the jury found Charles Kilmeister, James Oates, Edward Foley, John Russell, John Johnstone, William Hawkins and James Parry guilty of murder. Justice William Burton sentenced them to death on 5 December 1838, and Governor Gipps declined clemency. The seven men were hanged at Darlinghurst Gaol on 18 December 1838. The remaining four men initially charged, along with Fleming, were never convicted; the four were released in February 1839 after the prosecution's key Aboriginal witness, a boy named Davey, could not be located to testify, and Fleming was never captured or tried.
The case provoked strong public reaction in the colony, including editorials from some newspapers condemning the executions and defending the perpetrators. A memorial to the victims was unveiled near Bingara on 10 June 2000, and the massacre and memorial site were added to the Australian National Heritage List in 2008 and the New South Wales State Heritage Register in 2010. The memorial has been vandalised on more than one occasion, including in January 2005 and September 2021.