Anzac Day is celebrated on 25 April each year, regardless of on which day it falls. The day is a public holiday, however no replacement holiday is given if Anzac Day falls on a weekend (except in Western Australia).
It was on 25 April 1915 that the armies of Australia and New Zealand entered into their premier battle of the First World War, at Gallipoli, Turkey. At the time, Australia had only been recognised as a federal commonwealth for thirteen years.
Many Australians were sympathetic to the United Kingdom, which they regarded as the motherland. So the volunteer armies of Australian and New Zealand, eager to fight the good fight in the war, bravely landed on the shore of the Gallipoli Peninsula with the intent to capture and secure a safe passage for Allied navies.