Thousands gathered in Gallipoli as the Last Post echoed across the cove where the Anzacs faced a bloody slaughter in World War I with 2000 killed or wounded on the first day of the landing in 1915.
Representing Australia, Veterans Minister Matt Keogh said Gallipoli, in Turkey, where thousands died, had become a central part of the nation's story.
"Today, we gather to remember the sacrifices of so many ordinary Australians, caught up in extraordinary events throughout our history, the first of which, occurred on these shores," he said.
"Before the sun rose on that fateful day, the ANZAC legend was set in train. The legend that continues to shape our national values. Values of courage, sacrifice, compassion and mateship."
In Papua New Guinea, a service at the Bomana War Cemetery marked the more than 3300 Australians buried there.
In Ukraine, soldiers held the Australian flag in front of donated Bushmaster vehicles and Kyiv's envoy to Australia Vasyl Myroshnychenko paid tributes to fallen Anzacs, including the seven who died in the protection of his war-torn nation.
"To their families and friends we thank you. You are in our hearts and prayers. The efforts of these 'Ukrainian Anzacs' will not be forgotten," he said.
Back at home, the prime minister, Opposition Leader Peter Dutton said the service of Australians in Vietnam and Korea should always be remembered.
This year marks 50 years since the end of Australian involvement in the Vietnam conflict and 70 years since the Korean War came to an end.
"To this day, the Korean War can appear as a mere blip on the historical radar, receiving less attention than it should," Mr Dutton said.
"Narratives of shame and controversy continue to colour the Vietnam War. Our veterans deserve much better, our long dead deserve much better.
"In the case of Korea and Vietnam, let us never forget this: Australians fought in foreign lands to defend those who desired self-determination and liberty."
Mr Keogh acknowledged more needed to be done to ensure defence personnel were looked after following their service.
"We have a responsibility to look after our veterans, whether they've served overseas, whether they've come with injury or mental illness from that or served in Australia," he said.
"We're doing everything we can to look after them, but there's absolutely more to do."
Mr Keogh said the large numbers of people attending dawn services and commemorations across Australia and overseas reflected the recognition of service by broad sections of the community.
Defence Minister Richard Marles said Anzac Day was also a time to reflect on the 1200 Australians in military deployment.
On a recent trip to England, Mr Marles met with Australian defence personnel training Ukrainian troops to defend their country from Russia's invasion.
"To see people putting on the uniform of their nation, knowing full well that this might be a moment of personal and ultimate sacrifice is an extremely poignant and very inspiring thing to see," he said.
Lifeline 13 11 14
Open Arms 1800 011 046
