Yearning to reconnect with his heritage, he and his Welsh-born wife Sam, also an accomplished photographer, hatched a plan to document every one of the estimated 1000 marae in New Zealand.
They returned to Aotearoa with their three young children and spent three years travelling the country in a campervan, visiting as many marae as they could. They eventually notched up more than 300.
The book brings together their sumptuously detailed images, accounts of their experiences as they rekindle their links with the Maori world, and a series of recollections and essays by Bishop Walters about his childhood marae at Ahipara, the creation story and how it relates to the design of the wharenui, and how the contemporary meeting house evolved as a result of contact with Pakeha.
While trying to capture a cross section of marae by region and by iwi, the Walters also discovered a huge variety in styles and scale. Some marae are huge and ornately carved; others appear at first glance to be community halls cobbled together from corrugated iron.
As Robin explains, the marae in the book were chosen not for physical beauty but for their "spiritual magnificence".
The people and places that get the most space are those that most touched the Walters' hearts during their three-year journey.
As a result, Northland, the Walters' ancestral home, commands a large proportion of this book. Northland marae with chapters of their own include Korou Kore (Ahipara), Otiria (Moerewa), Ngati Manu (Karetu), Te Tii (Waitangi) and Potahi (Te Kao).
The authors then leap to Otago and Southland (who would have guessed that Bluff had such a flash marae, designed by master artist and carver Cliff Whiting of Russell?) before continuing their travels via the West Coast, Hawke's Bay, Wanganui, Te Urewera and East Cape (the wharenui at Whangara will be familiar to anyone who has seen the movie Whale Rider.)
Marae vividly captures the beauty and variety of New Zealand's meeting houses, but the photos I enjoy most are the portraits. Northlanders will recognise the faces of many old identities.
Summing up the family's photographic odyssey, Robin says Marae started as a book about the meeting house but turned into a book about the people of the meeting house. And, after rediscovering the richness of life on the marae, he calls on all New Zealanders to "give Maori culture a go."
-Marae: Te Tatau Pounamu
By Muru, Robin and Sam Walters
Godwit/Random House, 416 pages, hardback, rrp $80.