Rewi, or Manga as he was known to his kin, was the child of Paraheke (Te Kore) and Te Ngohi. His mother Paraheke was from Ngati Raukawa with close connections to Ngati Kaputuhi. His father Te Ngohi, also known as Kawhia, was a renowned fighting chief of Ngāti Paretekawa a sub-hapu of Ngati Apakura and was a signatory to the Treaty of Waitangi, one of five chiefs from Maniapoto who signed.
Maniapoto fought against General Cameron during the Waikato Campaign 1863-64 during the Land Wars. He made a final stand at Orakau in 1864. Rewi and the Kingitanga (Maori King Movement) rebels were surrounded by the government forces, with limited supplies of food and water. The government forces built a sap (trench) up to within 20m of the pā and threw in hand grenades. Gilbert Mair, an officer who spoke Maori fluently, invited them to surrender or at least let out the woman and children. The Kingites refused, saying they would fight on forever, but at 3:30pm the same day a gun was bought to the head of the sap and shelled the pā at point-blank range. At this the defenders panicked and, leaving 50 toa (warriors) in the pā, the rest made a sudden break through the government lines and into adjacent swamps. All 50 in the pā were killed or taken prisoner. 160 Kingitanga rebels died. Half of the escapees were wounded. Seventeen of the government forces died and 52 were wounded.
Maniapoto stayed in the King Country south of the Punui River with the surviving rebels. He constructed two more pā but the government forces did not follow him into the hills. Maniapoto played host to the rebel Waikato iwi (tribe) but relationships soured when the king tried to exert his mana over Maniapoto's land. This, together with Maniapoto's refusal to stand and fight at the battle of Rangiriri in 1863, left a bitter note between the two rebel groups. Rewi became concerned at the outbreaks of drunkenness among his people and the murdering of isolated Pakeha travelling in the area. Rewi reluctantly sheltered the rebel Te Kooti, who had escaped from the Chatham Islands and then attacked and killed various Maori and European settlers. When Te Kooti came to Te Kuiti in 1869 he came to challenge Tawhaio for Maori kingship. The king was hostile to Rewi's actions as he did not want the Kingitanga associated with Te Kooti's extreme violence and anti government activity yet he was very nervous of the Te Kooti's power to dominate. For months Rewi observed Te Kooti at close hand as the kingitanga were considering restarting the fight against the government. The kingitanga were impressed by Te Kooti's audacity. Te Kooti himself wanted to judge Te Kooti's military prowess before coming to some political arrangement with him. They offered Te Kooti the option of living in peace in the King Country but he refused. After his decisive defeat at Te Porere Rewi reported back that Te Kooti was no military genius. Magistrate William Searancke who spoke fluent Maori was present when Rewi met with Te Kooti and reported to the government that Te Kooti got very drunk and spoke at length about his past but not the future. Rewi Maniapoto remained sober and watchful. 
In 1877 MP John Sheehan became Native Minister. He was a fluent Maori speaker and had assisted East Coast Maori in the Repudiation Movement in their efforts to reclaim land they claimed had been wrongfully sold to large runholders. Sheehan has enhanced his reputation with Maori for backing them against government authority. He went to the King Country to talk to King Tawhaio and Taranaki chiefs to get them to sell land to the government but they refused . However he discovered that Rewi Maniapoto was keen to sell land. Initially the government's idea was to open up the land to European settlers to encourage assimilation. Eventually Rewi agreed to sell land to the government for the main trunk railway line on the understanding that his men would be paid to cut the bush for the surveyors and no alcohol was to be sold in the King Country. Maniapoto was returned his tribal land at Kihikihi and given a house and a government pension. He became a great friend of Governor Grey and wished to be buried with him.
Rewi Maniapoto used his connections with the government to help the renegade Te Kooti after he left his King Country sanctuary in 1889 and was arrested at Waioeka Pa near Opotiki. Te Kooti had been pardoned but had broken the conditions of his pardon and was trying to return to his East Coast home where he was highly unpopular with Maori and Pakeha alike. Te Kooti was jailed in Auckland but Rewi used his influence to persuade the authorities, not only to release Te Kooti, but to give him some land in Whanganui.
- Rewi Manga Maniapoto biography from the Dictionary of New Zealand Biography
- Biography in 1966 An Encyclopaedia of New Zealand