The Red Flag riots were a series of violent demonstrations and attacks that occurred in Brisbane, Australia over the course of 1918–19. The attacks were largely undertaken by returned soldiers from the First Australian Imperial Force (AIF) and were focused upon socialists and other elements of society that the ex-servicemen considered to be disloyal. The name was coined because of the flags that a number of the demonstrators carried, which were associated with the trade union movement and which were banned under the War Precautions Act. The most notable incident occurred on 24 March 1919, when a crowd of about 8,000 ex-servicemen clashed with police who were preventing them from attacking the Russian Hall in Merivale Street, South Brisbane.