The Forrest River massacre, or Oombulgurri massacre, is a disputed account of a massacre of Indigenous Australian people by a law enforcement party in the wake of the killing of a pastoralist, which took place in the Kimberley region of Western Australia in 1926. The massacre was investigated by a Royal Commission in 1927 which subsequently determined that 11 people had been killed. Charges were brought against two officers but dismissed for lack of evidence. A local man, Lumbia, was convicted of the killing of the pastoralist Frederick Hay. The findings have recently been disputed by journalist Rod Moran, whose analysis has received some academic support while other academic historians accept that a massacre did take place but disagree over the number of victims.
In 1921 two returned servicemen, Leonard Overheu and Frederick Hay, applied for a grant under the War Service Land Settlement Scheme. Nulla Nulla station was excised from the Marndoc Aboriginal reserve with the traditional owners, the King River Aborigines, removed and forced to live on the outskirts of Wyndham. The two men planted cotton, peanuts and kept a small herd of cattle. Hay, along with his friend James Dunnett ran the station while Overheu worked as a bookkeeper in Wyndham to provide cash flow. The first mention of Hay in the Forrest River Mission (later renamed Oombulgurri) diary was 27 May 1923 when an Aborigine reported that Hay had ambushed him and stabbed him repeatedly in the buttocks. The Rev. Ernest Gribble was later forced to assign guards whenever Hay visited the mission to prevent him from molesting the women and he wrote several complaints to the Protector of Aborigines A. O. Neville over Hay's behaviour. Another concern was that Hay had trained his dog to attack Aborigines. In January 1924 Hay seriously injured an Aborigine after hitting him over the head with his rifle butt. On 4 March he forcibly took Angelina from her husband and two weeks later mission staff informed Gribble that she was being forced to have sex with both Hay and Dunnett.