In the upcoming Maori Television documentary Shovels & Guns, historian Monty Soutar uncovers a controversial chapter in Dansey's military career - one that had a staggering effect on politics and race relations in New Zealand.
When Britain declared war on Germany in 1914, New Zealand was quick to offer help. Maori enlisted alongside Pakeha, despite the fact they had been fighting the British themselves just decades earlier. Soutar explains this about-turn, saying that since the land wars of the 19th century, Maori had been taught to revere the British Empire. They saw going to war as one of their Treaty of Waitangi obligations, and also as a natural part of their proud warrior tradition.
"[WWI offered] a way to fulfil their legacy," he said.
Dansey, then 29, was one of 500 men who formed the Native Contingent. They spent months training together in Auckland and represented the country's most athletic, well-educated young Maori. They left New Zealand eager to prove their valour on the battlefield.
What happened next was a "slap in the face", historian Christopher Pugsley says in Shovels & Guns. Instead of fighting on the front lines in Gallipoli, they were put on guard duty at the Malta Garrison and treated like an exotic oddity.
As the war raged on without them, Maori dug trenches - until so many soldiers had been killed that the British forces had no choice but to call for reinforcements. Under the command of Lieutenant Colonel Alfred Herbert, the Native Contingent travelled to Gallipoli. Dansey had already earned the respect of his comrades and been placed in command of A Company's 250 men.
Dansey in particular became known for his fearlessness. The determination he had once brought to the rugby field was now being put to use against the Turks.
"He fought like he played," one fellow soldier said at the time.
When the spine-chilling Ka Mate haka was performed on the battlefields of Gallipoli for the first time, it was thanks to Dansey and another soldier, Captain Pirimi Tahiwi.
"The Turkish soldiers thought that Satan was opening up the gates of hell ... when they heard Ka Mate ringing out," Massey University researcher Malcolm Mulholland says, quoting a newspaper article of the time.
But everything changed after the assault on Chunuk Bair in August 1915. Dansey and Herbert, his commanding officer, had a dramatic falling-out that resulted in Dansey and two other officers being sent home in disgrace.
Dansey's relatives insist he was unfairly persecuted - accused of cowardice for questioning orders that would have meant certain death for his men.
"There are numerous accounts of his courage and bravery," great-nephew Sean Dansey Ellison said.
"It wasn't cowardice."
But the details are hazy, so Soutar set out to uncover the truth about the clash between the two men. Along the way he uncovers remarkable new information, including a letter from Dansey to Herbert that is startling in its ferocity.
"The letter was on file at Archives NZ and it was only a matter of time before any experienced researcher worth their salt would find it," he said. "I thought, 'Well, this tells another story.'"
Dansey reluctantly returned to New Zealand, but his story wasn't over. As Soutar explains, what started as a personal conflict between Dansey and Herbert turned into a full-blown political crisis and public scandal.
Shovels & Guns details how Dansey and his fellow officers were eventually reinstated, thanks to vocal support from Maori and politicians.
"Once the impasse was over, the matter was put aside and the greater issue of winning the war became the focus," Soutar said.
However, he believes the controversy around Dansey changed the course of New Zealand history.
"The bad taste it caused led to a stronger push for senior Maori officers and Maori COs to be appointed to the 28th Maori Battalion in World War II. Sir Apirana Ngata [an MP from 1905 to 1943] fought hard and long to ensure that a repeat of the WWI experience did not occur."
Dansey eventually settled back in Rotorua, where he lived until his death in 1938.
The Dansey family remains in awe of their ancestor.
"Perhaps he might have been a naive soldier, but I fail to see how he was a coward," said great-nephew Mark Dansey. "He had the heart of a lion."
-Shovels & Guns screens on 7pm Anzac Day on Maori Television.