He was respected across iwi and government circles for his calm authority and his dedication to kaitiakitanga, particularly the protection of Tongariro, the sacred mountains first gifted to the Crown by his ancestor Horonuku Te Heuheu Tūkino IV in the 1880s.
His contributions were recognised in 2005 when he was made a Distinguished Companion of the New Zealand Order of Merit for services to conservation, and in 2009 he accepted redesignation as Sir under the Knight Companion rank.
He is married to Lady Susan Te Heuheu; they lived in Taupō.
Sir Tumu became the first New Zealander to chair UNESCO’s World Heritage Committee, elevating the Māori worldview in global heritage management.
He was instrumental in Tongariro National Park becoming one of the first places in the world to be granted dual World Heritage status, recognising both its cultural and natural values.
At home, he played a pivotal role in bringing iwi together on national issues, working closely with the Kīngitanga, and remained a steady leader through crises including the Covid-19 pandemic, advocating for whānau safety and ensuring Māori voices were central in responses.
“As we’ve seen from our own history with the 1917 influenza epidemic, in times of crisis we find strength and unity and pull together to support and tautoko one another.” He said at the time.
His last major public battle came just weeks ago, the return of Tongariro to Ngāti Tūwharetoa.
He said the government had failed to honour the intent of the original tuku of the maunga, urging ministers to respect the iwi’s role as guardians.
“Ngāti Tūwharetoa are tangata whenua. Our maunga are our responsibility,” he warned, that if talks stalled, legal avenues may be needed.
His final public appearance was at this year’s Koroneihana, the first for Te Arikinui Ngawai hono i te po, where he was warmly acknowledged for his decades of service.
Sir Tumu is survived by his whānau and the people of Ngāti Tūwharetoa, who will now begin the process of tangihanga for their rangatira.
Funeral arrangements are yet to be confirmed.