 An all volunteer force , by the end of the war the AIF had gained a reputation as being a well @-@ trained and highly effective military force , playing a significant role in the final Allied victory . However , this reputation came at a heavy cost with a casualty rate among the highest of any belligerent for the war . The AIF included the Australian Flying Corps ( AFC ) , which consisted of four combat and four training squadrons that were deployed to the United Kingdom , the Western Front and the Middle East throughout the war . After the war , the AFC evolved into the Royal Australian Air Force ; the remainder of the 1st AIF was disbanded between 1919 and 1921 . After the war the achievements of the AIF and its soldiers , known colloquially as " Diggers " , became central to the national mythology of the " Anzac legend " . Generally known at the time as the AIF , it is today referred to as the 1st AIF to it distinguish from the Second Australian Imperial Force raised during World War II . 
