Waterloo Plains massacre
1835 CE.
Shown on the map at -30.645°, 150.850°.
The Waterloo Plains massacre occurred in June 1838 when 8 to 23 Djadjawurrung Aboriginal people were killed in a reprisal raid for the killing of two convict servants and theft of sheep.
Text from the Wikipedia article Waterloo Plains massacre, licensed CC BY-SA 4.0.