Te Wheoro, who was later also known as Wiremu Te Mōrehu (William Morris) or Rehu, and also as Maipapa, was born in Waikato. His mother was Ngāpawa, and his father was Te Kanawa. Through Ngāpawa, Te Wheoro was descended from Te Whatu-o-te-rangi and Parengāope. He married Pākia and they appear to have had two daughters together; the first died of typhoid fever in her teenage years in 1879, around the same time as the birth of their second daughter, Te Kahukiwi te Pura Te Wherowhero (Te Pura or Waraki Ngāneko). Te Pura died in 1933. Te Wheoro succeeded Haripata Te Pō as chief of Ngāti Naho, who were closely connected to Ngāti Mahuta. He was also affiliated to Ngāti Hourua.
Little is known of Te Wheoro's early life, but his lineage, character and intelligence clearly gave him mana among Waikato people. At a great meeting at Paetai, near Rangiriri, in May 1857, where the proposal to install Te Wherowhero of Ngāti Mahuta as Māori king was discussed, Te Wheoro spoke in favour of the Pākehā governor, and against the title of 'King' which appeared to place Te Wherowhero above the governor. He supported F. D. Fenton, who was sent as resident magistrate to Waikato by Governor Thomas Gore Browne, until Fenton was recalled in 1858. He attended the conference of Māori leaders at Kohimarama in 1860, and spoke strongly and optimistically in favour of government policies.
Te Wheoro quickly adapted to Pākehā economic concepts and institutions. In 1862 he became the chief assessor, who acted as local magistrate and chief of police, in charge of the official rūnanga at Te Kohekohe, on the west bank of the Waikato River, south of Meremere. He asked that a wooden court-house be built there for magistrate John Gorst, and suggested that Māori youths be drilled to keep order. However, he was warned by Tāwhiao (King after Pōtatau Te Wherowhero's death in June 1860) that there would be trouble if buildings were erected, and when carpenters arrived from Auckland in March 1863 to begin building a fortified constabulary station at Te Kohekohe, 200 King supporters threw the timber into the river. One pile was saved when Te Wheoro's sister jumped onto it, and the Kingites withdrew. Ten days later, however, 100 of them returned, fully armed, and rafted the timber downstream, where they handed it back to the government at Te Ia (Havelock, near Mercer).
When war seemed imminent Te Wheoro moved his young men to Te Ia and established a pā there. He could not, however, prevent their supporting the Māori King when British forces invaded Waikato in July 1863. Lieutenant General Duncan Cameron appointed him a captain in the colonial militia, and used him as a guide. Te Wheoro and his remaining men provided an important link, collecting supplies from steamers at the Waikato Heads and paddling them upriver to the Camerontown redoubt, until the supply line was severed by a Ngāti Maniapoto attack in September 1863.
After the battle at Rangiriri in November, Te Wheoro began to act as intermediary between the government and the King movement. He went to Ngāruawāhia, under Governor George Grey's authorisation, to negotiate peace with Wiremu Tāmihana Tarapīpipi and Ngāti Maniapoto, and in the post-war years worked to reconcile King movement and government. However, the government confiscation of Waikato lands remained an obstacle to discussion while the King and his supporters were forced to live on Ngāti Maniapoto lands.
In April 1869 Te Wheoro was invited to meet leaders of the King movement at Tokangamutu (Te Kūiti). He proposed a meeting between the governor and the Māori King and his supporters at Ngāruawāhia in May, to which the visiting Duke of Edinburgh would be invited, but the King movement leaders did not attend. Te Wheoro became an assessor in the Native Land Court in 1865. He received a salary of £150 a year, but resigned in 1872, dissatisfied with what he later described as the corruption of a court that conferred title on those whom it thought most likely to sell the land. In 1873 he was appointed major in the colonial forces, against a background of increasing nervousness in the lower Waikato region, following the decision of Te Kooti to settle in Tokangamutu. Te Wheoro and 60 Ngāti Naho served as armed constabulary. They built and occupied the Ford redoubt, midway between Alexandra (Pirongia) and Kihikihi, commanding two fords on the Pūniu River, and formed a road between Alexandra and Orakau.
In 1875 Te Wheoro was appointed a native commissioner, and continued to assist in negotiations between the King movement and the government. In February 1875 he met and escorted Donald McLean, the native minister, to his Waitomo meeting with Tāwhiao, which Te Wheoro had arranged at Tāwhiao's request. At this time Te Wheoro was working with Major W. G. Mair, the resident magistrate at Alexandra, while Tāwhiao was living in Waitomo. Te Wheoro was also present at meetings between McLean and Tāwhiao in May 1876. In February 1878, at Tāwhiao's request, Te Wheoro arranged a meeting with Grey (now premier) at Te Kōpua. He escorted Grey and John Sheehan, the native minister, on the final part of their journey, and spent some time at Tāwhiao's side, but the meeting was largely unsuccessful in settling the King's grievances over confiscation.
Grey and Tāwhiao agreed to meet again at Hikurangi, near Kāwhia, but it took much work on the part of Te Wheoro to persuade Waikato to engage in more negotiations with the government. Only when it was agreed that Rewi Maniapoto would host Grey did Tāwhiao and his adviser, Te Ngākau, ask Te Wheoro to arrange a meeting. On 9 April government ministers arrived at Hikurangi, but were made unwelcome. They returned to Auckland, where Te Wheoro arrived a week later with a further invitation, which he had persuaded Tāwhiao to extend. The meeting finally took place on 7 May. Te Wheoro urged the parties to dispense with trivia and speak frankly to one another. Grey proposed that Tāwhiao should be a paid administrator within his own district. He offered the King 500 acres at Ngāruawāhia, a meeting house at Kāwhia, and the return of confiscated land on the west side of the Waikato and Waipa rivers not already sold to Europeans. Road building would be negotiated by both parties, and Tāwhiao would decide whether surveying should take place. However, the issue of confiscated lands again prevented much progress. Te Wheoro himself had lengthy but inconclusive discussions in 1878 with F. D. Fenton, now chief judge of the Native Land Court, on the return of his own tribal land, which had also been a part of the Waikato confiscations.
In December 1878 Tāwhiao and his chiefs embarked on a tour of Waikato and Whāingaroa (Raglan Harbour). Te Wheoro accompanied them as a government representative. Tāwhiao and Rewi had arranged another meeting with Grey at Te Kōpua in May 1879. There, when Tāwhiao reasserted that his title and descent gave him the right of guardianship over the whole of the North Island, not only Waikato, he and Te Wheoro parted company. Grey was referred to in hostile terms and given no speaking rights. Te Wheoro and other chiefs interceded for him, invoking the proposals made at Hikurangi, but it was to be the last opportunity for any reconciliation between Grey and the King.
Te Wheoro resigned as a native commissioner in 1879, feeling that he was not listened to, and that his people were treated unfairly. On 8 September 1879 he was elected to Parliament as the representative for Western Māori, on the nomination of Rewi, who helped him secure 1,053 of the 1,494 eligible votes cast. Rewi assumed that Te Wheoro, as a firm friend of Sir George Grey, would support Grey as premier. It was reported, however, that Te Wheoro only took part in the vote for the government in October after being locked in. His intention had been not to vote at all. In any event Grey lost the election and had only a short time to remain as premier. When John Hall took over as premier in the same month, Te Wheoro refused to join his ministry because Māori members were not to be given responsible portfolios.
In Parliament Te Wheoro became a member of the Native Affairs Committee, and was soon in conflict with the native minister, John Bryce. In 1880 Te Wheoro attacked the working of the Native Land Court, government attitudes towards the Māori, and the structure of the Native Affairs Committee itself. He voted for a new land court bill, which, he felt, though imperfect, must be an improvement on the old. In 1881 he attacked the Crown and Native Lands Rating Bill as contrary to the Treaty of Waitangi and labelled it the 'Mortgage and Confiscation of Native Lands Bill'. On its second reading in 1882 he accused the government of racial hypocrisy and blatant land-grabbing. In September Bryce threatened to disband the Native Affairs Committee. Te Wheoro replied that as the committee was powerless and of no help to the Māori he did not care. He challenged anyone to name a Māori application to government that had been granted.
Te Wheoro was well informed and mindful of the interests of his constituents. He succeeded in having the government translate the Hansard reports of the speeches of Māori members back into Māori for distribution among the constituents. He was a supporter of the temperance movement, and entreated the government to ban liquor from Māori districts. He favoured local self-government for his people, and Māori retention of their lands.
He petitioned the Native Affairs Committee three times in 1881 and twice in 1882 for the return of the confiscated land of his hapū. He also petitioned for a Crown grant to make an area of land at Karioi inalienable from his hapū except through lease, and consistently argued that this solution should be applied to all Māori land.
Throughout his time in Parliament Te Wheoro remained closely associated with Tāwhiao, acting as his envoy to government. When in 1882 the King and Rewi disagreed over the establishment of a land court at Mōkau, a meeting was called at Whatiwhatihoe. Te Wheoro accepted the task of representing Tāwhiao's position to the government: that land dealing, surveying and roadmaking be stopped, and the court at Mōkau abandoned. He also tried to persuade Rewi that he could make no impression on Parliament while Ngāti Maniapoto were still dealing in land.
In February 1883, when the government, with the support of Ngāti Maniapoto, began a survey of Kāwhia, where both Te Wheoro and Tāwhiao claimed much land, Te Wheoro protested vigorously. It was rumoured that he was inciting obstruction of the survey. He asked that he and Tāwhiao be allowed to conduct the survey themselves, and was told by Bryce to take his claim to the Native Land Court. He fought for an inquiry into the validity of the government purchase, and unsuccessfully opposed the bill proposing sale of sections in the township. From the frustration of this defeat was born the idea of making an appeal to Queen Victoria herself on behalf of her Māori subjects; it was almost certainly on Te Wheoro's initiative that in July 1883 a letter signed by the four Māori MHRs was dispatched to the Aborigines Protection Society in London. The letter suggested a visit to England by Tāwhiao the following year to appeal to the Queen, a party to the Treaty of Waitangi. For some time Te Wheoro's inclusion in the travelling party was in doubt, but representations from Tāwhiao and his people eventually persuaded him to depart with them on the Tarawera on 1 April 1884.
In England the party was received by the secretary of state for the colonies, Lord Derby, but not by the Queen. John Gorst, now a British MP, introduced Te Wheoro as a loyal chief who had lost all his tribal lands, and despite repeated promises, had never received compensation, nor had any land been returned. Te Wheoro made a fluent and forceful speech, outlining his appointment to positions which he had hoped would enable him to help his people, and his eventual disillusionment with each. He maintained that the Māori members carried no weight in the House of Representatives and were therefore appealing directly to the Queen for redress.
Te Wheoro vetted those who wished to visit Tāwhiao in England, and when the King returned to New Zealand in August, Te Wheoro remained behind to await in vain a response to the petitions. He returned home in poor health, late in 1884.
In the 1884 election, while he was overseas, Te Wheoro lost his seat in Parliament and missed a court hearing over land he claimed at Maungatautari. He arrived back in Waikato late in January 1885. At a meeting at Alexandra on 7 February he informed the native minister, John Ballance, that he hoped the government's policies, especially with regard to Kāwhia, would change. He requested that bills concerning Māori be submitted to the British government, and asked for local Māori self-government, and control over lands on which railways were being built. He unsuccessfully sought a rehearing on his Maungatautari case a few days later. He was devoted to restoring the mana of the King, and cited the Maungatautari case as a clear indication of the corruption of the land court. (The native assessor had been bribed.)
By 1886 he and Tāwhiao were in clear conflict with Ballance over Kāwhia. He considered Ballance no friend of the Māori, as the Native Land Court at Taupō and the Kāwhia survey had continued, despite Māori protests. But Te Wheoro told his people to remain firm, as governments must change, and the next one might be more responsive.
Te Wheoro was one of John White's major informants for his six volume compilation The ancient history of the Māori (Wellington, 1887–90). In January 1890 he visited Auckland, with other Waikato chiefs, for the celebration of the 50th anniversary of the signing of the Treaty of Waitangi. Despite his increasing disillusionment with the operation of Pākehā institutions, he read a speech wishing the new governor, Lord Onslow, well, and expressing happiness at the European presence in the country.
Te Wheoro died on 30 October 1895 at his home at Te Ārai, near Churchill. He is said to have been about 69 years of age. He was originally buried at Maurea in Rangiriri but later moved to Taupiri Mountain.