"I told Len Brown, who set it up, that I wanted to expose the secret history of Auckland and New Zealand."
The book tells the story of the Great South Road, built from Auckland through the Waikato by the British army that invaded Māori territories in 1863.
After the British and local Pākehā soldiers had defeated Māori in the Waikato War, more than a million acres of Māori land was confiscated.
"The invasion of the Waikato was legitimated by racism and it has cast a long shadow," Hamilton said.
Looking at archives and old newspapers, he discovered Māori were treated as "enemies of the state", long after the Waikato War had finished.
"During a series of epidemics, Māori were banned from moving about the country, because their brown skin was equated with disease," Hamilton said.
"When smallpox broke out in 1913, Māori villages were sealed off, and Māori were banned from the roads and from trains unless they had a special certificate showing they'd been immunised.
"No Pākehā was ever subjected to these rules. They were blatantly racist, made life almost impossible for Māori, and were in force for many months."
Māori were also excluded from bars, cinemas and barber shops in South Auckland.
"For much of the 20th century it was hard to get a drink in places like Papakura and Pukekohe if you were the wrong colour," Hamilton said.
The book details the experience of Rongomanu Bennett, a Māori psychiatrist who was refused a beer in the Papakura Tavern in 1959.
He began a campaign and made headlines around the world.
"The New York Times called Papakura 'the Little Rock of New Zealand', after the Arkansas city where African Americans were fighting segregation," Hamilton said.
The Prime Minister at the time eventually backed up Bennett, and Papakura Tavern agreed to serve Māori.
But this civil rights struggle in South Auckland, and the racism that prompted it, had been forgotten, Hamilton said.
"If more of us knew about what happened in the past, then we'd understand the
historical context for Taika Waititi's complaints about continuing racism," Hamilton said.
"Papakura is still not the most friendly place for Māori. The local board there made it difficult to build a marae in the 1970s and 1980s, and recently the community board rejected attempts to set up a Māori advisory committee to help it learn from the mistakes of the past."
The book also includes stories about friendships across ethnic lines, and celebrated the cultural diversity of 21st-century Auckland.
One was about Michael O'Connor, an Irishman who opposed the British Empire.
In the 1870s he created his own private army and formed an alliance with the Māori King Tawhiao, and also supported Te Kooti.
"The story shows how strange and rich our history is," Hamilton said.
"If you're a Pākehā, then you may have had ancestors who conquered the world with the British Empire, but you probably had other ancestors who were rebels, like Michael O'Connor.
"You're free to identify with whomever you like."
