In the days leading up to his death, Tāwhiao, the second Māori king, made known his choice of successor with these words:
Papa te whaitiri, ka puta Uenuku, ka puta Matariki. Ko Mahuta te kingi!
The thunder crashes, Uenuku appears, Matariki appears. Mahuta is the king!1
Mahuta remained the head of the Kauhanganui (Kīngitanga parliament), which continued to meet. In the 1890s his movement attempted to unite with the Kotahitanga (Māori parliament movement), without success. At one meeting with the Kotahitanga in 1895 the Kīngitanga was invited to sign the Kotahitanga deed of union. Instead, a rival Kīngitanga deed, later known as Mahuta's deed, was drafted and signed by 5,000 people.
In 1898 the Western Māori MP Hēnare Kaihau, who was under Mahuta’s patronage, introduce to Parliament a Maori Council Constitution Bill, which provided for a form of Māori self-government. However, the bill was discharged before its second reading.
Mahuta increasingly looked to bring Māori and Pākehā closer together. Perceiving an opportunity to influence the government, in 1903 he accepted Premier Richard Seddon’s offer of a seat on the Legislative Council and a position in the ministry. Seddon hoped to win over the King movement and free up more Māori land for purchase. However, in 1906, in a rare speech in Parliament, Mahuta stated that it ‘was not sufficient merely to open up Maori lands for European settlement. Parliament should enable the Maori to work his lands.’2
During his time in the legislature, Mahuta temporarily passed on the kingship to his younger brother, Te Wherowhero Tāwhiao. When Mahuta’s term ended in 1910 he resumed his kingship.
Aspiring Ngāti Porou politician Apirana Ngata made this assessment of Mahuta in 1900:
The King of Waikato (Mahuta) is a personage who can well bear the honourable title, and in whom the hopes of those within the circumference of the King Movement may well be centred. He has personality, but more he is a thinker. To me he is keen to discern, quick to consider good advice, and diplomatic, perhaps somewhat stunted by the authority of custom prevalent in that Waikato region. I think he has shown initiative in advance of his people, striving to turn to their advantage those things of worth in the European way of life.3
King Mahuta died on 9 November 1912. During his tangihanga, when all the rangatira had assembled, the question of Mahuta’s successor was considered. The leaders chose his eldest son, Te Rata, whose investiture was carried out before Mahuta was buried on Taupiri mountain.