First musket wars
In 1821 Waikato expelled Ngāti Toa chief Te Rauparaha from Kāwhia after much intertribal fighting between Ngāti Toa and Waikato peoples. A number of times peace had been made, but broken afterwards as war resumed. The same year Waikato defeated Ngāti Tama at Pārāwera.
Later that year Waikato under Te Wherowhero sought to attack Te Rauparaha at Ōkoki in North Taranaki. Te Rauparaha sent out a decoy party which led Waikato into a trap and they were defeated. Te Wherowhero was about to be shot but Te Rauparaha kicked the musket aside, allowing him to engage in one-on-one combat.
Hawke’s Bay and Taranaki
In 1824 Waikato allied with Te Heuheu of Ngāti Tūwharetoa to defeat Ngāti Kahungunu at Te Pakake (Napier). Waikato took captive some of the most important Hawke's Bay chiefs, Takamoana, Tareha, Pāora Kaiwhata, Te Hāpuku, Tiakitai and Kurupō Te Moananui. They were released around 18 months later by Te Wherowhero.
In 1826 Waikato invaded Taranaki, forcing a number of tribal groups to move south. In 1828 at Te Pane o Horoiwi, Ngāti Tipa of Waikato and Ngāti Pāoa of Hauraki defeated a Ngāpuhi war party led by Rangituke. That same year Paiaka of Waikato, along with Te Heuheu and Te Whatanui, attacked Te Wera Hauraki and Te Pareihe at Kaiuku pā, Māhia. Te Wherowhero invaded the Whāngārei area and fought at Ōparakau.
In 1830 Ngāi Te Rangi and Ngāti Hauā under the great Waikato general Te Waharoa attacked Ngāti Maru at Taumatawiwi in Waikato. Ngāti Maru left the region as a result. In 1831 a Ngāpuhi war party led by Te Haramiti was beaten by Ngāti Hauā and Ngāi Te Rangi following an attack on Tūhua (Mayor Island).
In 1831–32 Te Wherowhero of Waikato captured Pukerangiora, a Te Āti Awa pā in north Taranaki. At Ngāmotu pā, at present-day New Plymouth, Te Āti Awa managed to hold out against Waikato. In 1832 Te Wherowhero attacked Ngāpuhi at Tutukākā, north of Whāngārei. The same year he again attacked Taranaki at Mikotahi pā (New Plymouth). At Te Namu, on the Taranaki coast, Waikato were beaten back by Taranaki forces under Te Matakatea. In 1834 Te Wherowhero attacked Te Ruaki in southern Taranaki. In 1836 Te Waharoa attacked Te Arawa pā at Maketū in the Bay of Plenty. He died in 1838.
End of the wars
Waikato ended the wars successfully, having largely defended their territory against northern incursions. They had also expelled Ngāti Toa, Ngāti Maru and a significant number of Ngāti Raukawa. Their chief, Te Wherowhero, was renowned as a military leader.