Torres Strait, Australia (CNN)Almost every able-bodied Indigenous man throughout Australia's Torres Strait Islands signed up to defend their country against the threat of invasion during World War II, despite not being recognized as citizens.
Australia's forgotten indigenous World War II veterans
The country's first and only all Indigenous army unit, the Torres Strait Light Infantry Battalion, was formed in 1943 as the Japanese Imperial army menaced Australia's northern coastline.
Approximately 880 recruits enlisted, from an estimated able-bodied male Indigenous population of 890, across the Torres Strait island chain -- an Australian sea territory between the northern tip of the state of Queensland, and southern Papua New Guinea.
Speaking on the 75th anniversary of the battalion's founding in March, Australia's Chief of Army Lt. Gen. Angus Campbell said it was possibly the highest rate of voluntarism in the whole country, per capita, during the WWII.
At the time, there were only around 4,000 people dotted across the island chain, although exact figures are hazy as indigenous people weren't included in the census at the time. In comparison, Australia's population stood at over seven million.
Now, only three of the original members of that unit survive. Campbell said it was important to honor their sacrifice.
"There is no other part of this country that served at such a great rate, we owe an extraordinary debt of gratitude and acknowledgment to these men and what they gave for their country," he said during the event held on Thursday Island in the Torres Strait on March 17 this year.
Every April 25, Australia commemorates the sacrifices of its military servicemen and women on Anzac Day, including the Indigenous Australians who have fought in every conflict since the Boer War.
Originally created to honor the members of the Australian and New Zealand Army Corps (ANZAC) who fought during the doomed Gallipoli campaign in World War I, it has become a day of remembrance for all Australian troops, or "diggers" as they are known.
Australia's "black diggers," or Aboriginal and Torres Strait Islander soldiers, fought the same wars but not for the same privileges.