Piupiu Te Wherowhero was born, probably in 1886 or 1887, at Whatiwhatihoe, Waikato. She was the daughter of Te Wherowhero Tāwhiao of Ngāti Mahuta, the third child and second son of the second Māori King, Tāwhiao Matutaera Pōtatau Te Wherowhero. Her mother was Tamirangi Manahi of Ngāti Tamaoho of Te Kūiti.
Little has been recorded of Piupiu's childhood and upbringing, although she may have attended primary school in Mercer for a time. Like her cousin Te Puea Hērangi, she had an imperious, strong-willed character. She was regarded as a princess in the popular European press, and her status, already high in Māori opinion, was raised still further by the fact that her uncle Mahuta, the third Māori King, delegated the kingship to her father from 1903 until 1910 while he served in the cabinet and on the Legislative Council. Piupiu grew up accustomed to the highest honours and deference within an atmosphere of tapu and religious awe on official occasions. She herself sometimes dressed in the height of fashion. But the Māori kingdom had little means of financial support and through land confiscation its people were often poorer than Māori in other tribal areas. There were times when with Te Puea and the other women she worked in the fields and the kitchens.
Piupiu's father died late in 1911 and Mahuta 11 months later. The new King, Te Rata, suffered from chronic illnesses and was of a retiring disposition. The women of the kāhui ariki (royal family), including Te Marae (Te Rata's mother), Te Puea and Piupiu herself, took leading roles in his reign. It was probably Te Marae who arranged Piupiu's marriage to Kainuku Vaikai, a kinsman of the Mākea Nui ariki family of Rarotonga. Piupiu made a second marriage to Hīroka Hetet, also known as Hīkaka Hetet, whose parents were Ngātai Ruihi Hetet and Mata Lana, both of Ngāti Maniapoto with Ngāti Tūwharetoa connections. After this she was often known as Piupiu Hetet. There were children of both marriages.
While living among Ngāti Maniapoto, Piupiu came into contact with the Rātana faith. With Tupu Taingakawa and her uncle Haunui Tāwhiao – her closest associate among the family – she was the leader of a strong pocket of Rātana adherents within the King movement. Piupiu presented herself to Rātana as one who could draw Te Rata into the Rātana movement. In September 1922 she was undoubtedly present at Waahi during a disastrous attempt at reconciliation between the two leaders. During this visit the proper protocol was ignored by the Rātana contingent, and the King and his followers considered themselves belittled; a serious division developed between the Rātana and King movements which was never fully to heal in Piupiu's lifetime.
Piupiu went her own way within the King movement. Throughout her life she continued her adherence to Rātana, and with Haunui Tāwhiao, hosted Rātana hui, inviting guests as though she spoke for the movement as a whole. These actions provoked frequent quarrels with Te Puea, who was unsure whether to regard Rātana as a prophet or a charlatan, and was opposed to attempts by Piupiu and the Rātana faction to dominate the King movement.
Like Te Puea, Piupiu saw the landlessness, homelessness, disease and poverty among her people, and took similar steps to combat these evils. Probably in the 1920s, with the encouragement of Te Rata, Piupiu set up a new community, originally called Kēnana (Canaan), on land she owned. Its first houses were made of sacking; chairs were benzine boxes. There was no government or other assistance. Its people struggled to break in land, sow grass and purchase and farm dairy herds, besides raising subsistence food crops such as potatoes, kūmara, pumpkin, marrow and corn. The ground was swampy and liable to flooding, and Piupiu later moved the settlement to higher ground. Unlike Te Puea's, Piupiu's efforts were not covered by the Pākehā press, and all her life she struggled in relative obscurity.
In 1931 Piupiu sponsored Pēpene Eketone, an adherent of Rātana, as the parliamentary candidate for Western Māori; in so doing she was opposing the rest of the kāhui ariki who still favoured Māui Pōmare. In 1928 Rātana himself had favoured his own son, Tokouru, although he had been willing for a period to resign the seat to Te Rata's nominee. This kind of ambivalence probably extended into the 1931 election, and in these circumstances Piupiu was able to support Eketone.
In his last years, 1932 and 1933, Te Rata made an effort to wean Piupiu away from her Rātana allegiance. But Piupiu and Haunui persisted in their own efforts to draw him to the Rātana faith. By 1934 Piupiu was exerting her influence over Te Rata's heir, the new King, Korokī, and was soon involved in a fresh controversy. Haunui and Piupiu had persuaded Korokī to visit Rātana pa instead of accepting an invitation by Ngāti Porou to open their new house at Tokomaru Bay. When a visiting party of Rarotongan nobility was invited to open it instead, Te Puea and other members of the King movement leadership took offence, and a tremendous quarrel ensued among the kāhui ariki. Apirana Ngata, escorting the Rarotongan party, managed to effect a reconciliation between the King movement factions.
Piupiu Te Wherowhero died, aged 50, on 29 October 1937 at Arapuni. She was survived by Hīkaka Hetet, who died in 1959, and by 10 children. She was buried on Taupiri Mountain on 2 November. Independent, determined and capable, she symbolised a number of struggles: for survival and reconstruction among an impoverished people made helpless through land confiscations; and for recognition of the Rātana faith among the leadership and people of the King movement. She exemplified, also, the strong leadership qualities shown by many women of the Waikato kāhui ariki.