Te Rauparaha became one of New Zealand’s first political detainees when he was seized during the fighting in the Hutt Valley in 1846. Other Māori leaders who faced similar treatment during the 19th century included Te Kooti, Te Whiti and Tohu Kākahi.
Another detainee was Hohepa Te Umuroa (Ngāti Hau of Te Āti Haunui-a-Pāpārangi). In 1846, Te Umuroa and a number of Whanganui Māori joined Te Rangihaeata’s armed resistance to the European settlement of the Hutt Valley. He took part in Te Mamaku’s attack on Boulcott’s Farm in May. On 14 August 1846, Te Umuroa and six other Whanganui Māori – Te Waretiti, Matiu Tikiaki, Te Kumete, Topi, Matai-umu and Te Rahui – were captured by a party of Te Ātiawa at Paripari in the hills north of Pāuatahanui. Te Ātiawa were pursuing supporters of Te Rangihaeata who were retreating from Battle Hill.
With martial law still in force, Governor Grey charged the seven men with rebellion against the Queen. None of the accused spoke sufficient English to adequately defend themselves. With no legal representation, they had only an interpreter to plead their case. They pleaded guilty. On 12 October 1846 they were sentenced to be ‘transported as Felons for the Term of their Natural lives.
Matiu Tikiaki and Topi were kept in Auckland as possible witnesses in a trial of Te Rauparaha which never eventuated. The other five were sent to a penal colony in Van Diemen’s Land (Tasmania). They arrived in Hobart aboard the Castor on 16 November 1846 and were sent to Darlington probation station, on Maria Island. They were given separate huts from the main dormitory, which housed 400 convicts.
In April 1847 Te Umuroa became sick with tuberculosis; he died on 19 July. He was buried in the small public cemetery on the island. The prison foreman, J.J. Imrie, read the funeral service in Māori at the graveside. An anonymous benefactor later erected a headstone over the grave.
In the wake of Te Umuroa’s death the acting Lieutenant-Governor of Van Diemen's Land, C.J. La Trobe, and the Colonial Office questioned the legality of the original court martial. The transportation of the Māori captives had been questioned by the Hobart press when the prisoners first arrived, and opposition to the punishment increased with Te Umuroa’s death. The four remaining prisoners were released and returned to Auckland in March 1848. Te Umuroa had a longer wait for his return. Six elders from his iwi accompanied his remains home from Tasmania in 1988. He was reburied on 8 August that year at Roma cemetery in Jerusalem, on the Whanganui River.