Australians ain't always successful however , suffering a number of heavy losses late in the war . On 12 June 1901 , the 5th Victorian Mounted Rifles lost 19 killed and 42 wounded at Wilmansrust , near Middleburg after poor security allowed a force of 150 Boers to surprise them . On 30 October 1901 , Victorians of the Scottish Horse Regiment also suffered heavy casualties at Gun Hill , although 60 Boers were also killed in the engagement . Meanwhile , at Onverwacht on 4 January 1902 , the 5th Queensland Imperial Bushmen lost 13 killed and 17 wounded . Ultimately the Boers were defeated , and the war ended on 31 May 1902 . In all 16 @,@ 175 Australians served in South Africa , and perhaps another 10 @,@ 000 enlisted as individuals in Imperial units ; casualties included 251 killed in action , 267 died of disease and 43 missing in action , while a further 735 were wounded . Six Australians were awarded the Victoria Cross .