The ritual killing by Pai Marire followers of missionary Carl Völkner in 1865 shocked many people. The government used the event as a reason to take harsh action against Pai Marire in general.
On 2 March 1865 the missionary Carl Völkner was hanged from a willow tree near his church at Opotiki. His death was attributed to the followers of Pai Marire who had recently arrived in the area.
German-born Carl Völkner was in charge of the Church Missionary Society mission station at Opotiki . Following several visits to Auckland in 1864 and early 1865 rumours spread among Pai Marire followers that Völkner was a government spy. Locals warned him to stay away from the mission station but he returned to Opotiki with fellow missionary Thomas Grace on 1 March 1865. Both were taken prisoner.
Völkner was hanged from a willow tree near his church by members of his own congregation, Te Whakatohea. His head was then cut off and many of those present either tasted his blood or smeared it on their faces. In a final insult Kereopa Te Rau swallowed Völkner's eyes, describing one eye as 'Parliament' and the other as the 'Queen and English law'. Thomas Grace was spared.
Kereopa Te Rau was one of the five original disciples of Te Ua Haumene. During the Waikato War his wife and two daughters had been killed at Rangiaowhia. A sister was killed during the fighting at Hairini. Following his conversion to Pai Marire, he and Patara Raukatauri had been sent by Te Ua to the East Coast to spread the word. Twice on this journey Kereopa had demanded that Europeans be given up to him. He was denied on both occasions. Kereopa may well have instigated Völkner's death but it is not clear whether he particpated in the actual killing. His actions in eating Völkner's eyes clearly outraged Europeans but committing an indignity to the head of an enemy in this way conferred mana on him. In a battle against Ngati Manawa in May 1865 three warriors were killed and decapitated. According to one account Kereopa repeated his eye-eating act, earning himself the name Kaiwhatu (the eye eater).
Not surprisingly, this event sparked outrage amongst the settler community and sections of Maori society. The government responded to the killing and general disturbances in the area by confiscating 144,000 acres (about 58,000 hectares) of Te Whakatohea land under the terms of the New Zealand Settlements Act 1863. In the process, it also satisfied settler demands for land.
Kereopa took sanctuary in the Urewera region before being taken into custody in September 1871. He stood trial in Napier for the murder of Völkner. While there was no direct proof of his responsibility for the killing, a European witness testified that he had seen Kereopa among those who escorted Völkner to the willow tree. On the basis of this testimony Kereopa was convicted and sentenced to death. William Colenso argued for clemency on the grounds that the crime had already been punished by other executions and land confiscation. His calls were unsuccessful. Kereopa spent his last night in the company of Mother Mary Aubert and was hanged on 5 January 1872.