Pōtatau set a boundary separating his authority from that of the governor: 'Let Maungatautari be our boundary. Do not encroach on this side. Likewise I am not to set a foot on that side.' His aim was not to oppose the Crown but instead provide authority in the lands placed under his mana (authority). Supporters believed it was possible for the mana of both monarchs to be complementary. To Māori, the Kīngitanga was a development for Māori, not against Europeans.
Given the tribal nature of Māori society there was some surprise that a pan-tribal movement had been established. Most Māori were loyal to their own hapu first and foremost. The historian Michael King believed that as the European population grew it created a sense of Māoriness that made it possible for Māori to distinguish between a Māori and non-Māori world and think beyond their tribal affiliations. A perceived strength of the British lay in their unity under the Crown, and supporters of the Kīngitanga believed that if Maori could replicate this sense of unity then they stood a better chance of withstanding the full impact of colonisation.
Despite this, important iwi like Nga Puhi, Te Arawa and Ngati Porou did not join. Some opponents dismissed the Kīngitanga as a Waikato movement that had little support in other parts of the country. Historian James Belich maintained that the Kīngitanga did not represent a radical change in the North Island. 'It was not a declaration of Māori independence – this already existed – and it added no new territory to the Māori sphere. It sought merely to unite pre-existing polities. But in other ways the Movement was an important change. Together with the rise in anti-land-selling generally, it raised the profile of Māori independence from a level which the British disliked but tolerated, to a level which many found entirely unacceptable.'
When fighting broke out between government forces and supporters of Wiremu Kingi in Taranaki in April 1860, the Kīngitanga was portrayed as being behind the war. Most Kīngitanga supporters in lower Waikato, including Pōtatau himself, actually opposed involvement in the Taranaki War, but when Ngati Maniapoto warriors arrived to help Kingi's men, the finger of blame was pointed in the direction of Waikato.
Some settlers and politicians saw this as an opportunity to assemble all the so-called troublemakers together and crush them in one hit. This never happened, and events in Taranaki quickly reached a stalemate.
The Kīngitanga resisted further European encroachment and opposed new roads, and it sought self-government in Māori areas. The movement took on the appearance of an alternative government with its own flag, newspaper (Te Hokioi), councillors, magistrates and law enforcement. The Kīngitanga government even had a minister for Pakeha affairs.