The Day of Mourning was a protest held by Aboriginal Australians on 26 January 1938, the 150th anniversary of the arrival of the First Fleet, which marked the beginning of the colonisation of Australia. It was declared to be a protest of 150 years of callous treatment and the seizure of land and purposefully coincided with Australia Day celebrations. The protest became a tradition, and annual Days of Mourning have been held to this day.