Te Kani-ā-Takirau was of Te Aitanga-a-Hauiti of Ngāti Porou. Born near the end of the eighteenth century, probably on the East Coast, he lived most of his life at Ūawa (Tolaga Bay). His mother was Ngārangikahiwa, the daughter of Hinematioro; his father was Rongotūmamao, the son of Te Whakatatare-o-te-rangi, the chief who met Captain James Cook at Ūawa. Several descent lines of great importance to Ngāti Porou converged in the person of Te Kani-ā-Takirau. Held in reverence from Cook Strait to Bay of Plenty and described as resembling the priest-kings of central Polynesia, he had a regal bearing and was famous for his generosity.
Te Kani-ā-Takirau never grew his own food, was waited on and fed by a few people of high rank, and was accompanied by a guard of honour when he travelled. If he was in danger of being captured, a bodyguard of warriors would find a way to take him to safety. He is said to have fought Ngāpuhi and Waikato at the Waipaoa River in 1820, and to have escaped in a canoe. Later he became an ally of Ngāpuhi chief Te Wera Hauraki, and fought against a section of Ngāti Porou. However, he is not known as a great war leader, possibly because his people were reluctant for him to risk his life: he failed to lift the siege of Pukekaroro pā in the mid 1820s and withdrew from the siege of Toka-ā-Kuku in 1836.
Te Kani-ā-Takirau was friendly towards European traders and encouraged Te Whānau-a-Ruataupare hapū to move to Ūawa to trade in flax. In the 1830s a small settlement grew up at the bay under his patronage, but he kept the two European traders on opposite sides of the Ūawa River to prevent rivalry. He never became a Christian, although he protected the mission that was established at Ūawa in 1843. On one occasion, without any supporters, he ordered away an armed party who were planning to burn the home of the CMS missionary Charles Baker. From the end of 1848 he attended church services, not through commitment to Christianity but because 'his people took advantage of his being disconnected with the Christian party to treat him with neglect and scorn'. He also accepted missionary mediation in disputes, as in 1852 when he declared war on the Tūranga (Gisborne) Māori after a post was removed from a burial ground of his ancestors. For some time the roads between Tūranga and Ūawa could not be used because he had placed a ban on them.
It is possible that Te Kani-ā-Takirau did not become Christian because he had more than one wife. His first wife was Mariko; another was named Amotawa; and a third was Hineitīeria-te-rangi: he may have had as many as ten wives. He had two children, one of whom was a son, Te Waikari; both children died before him and without issue.
Although the CMS missionary William Williams, bearing a copy of the Treaty of Waitangi, visited Te Kani-ā-Takirau on 16 May 1840, the chief did not sign the treaty. Later, according to East Coast tradition, he was offered the Māori kingship but declined, saying: 'My kingship comes from my long line of ancestors. My mountain Hikurangi is not one that moves, but one that remains steadfast.' A major leader of his people, he was suggesting that he needed no additional titles, and that his place was with Ngāti Porou.
After a long illness Te Kani-ā-Takirau died at Whāngārā, probably in 1856. His tangi was held in the traditional manner; William Williams read the evening prayers. He is believed to be buried at Te Ana-a-Paikea (Whāngārā Island), near his grandmother Hinematioro.