The First Taranaki War (also known as the North Taranaki War) was an armed conflict over land ownership and sovereignty that took place between Māori and the Colony of New Zealand in the Taranaki region of New Zealand's North Island from March 1860 to March 1861.

The war was sparked by a dispute between the colonial government and the Te Āti Awa people, led by Wiremu Kīngi Te Rangitāke, over the disputed sale of the Pekapeka land block at Waitara. The deal was orchestrated by minor Te Āti Awa rangatira Te Teira Manuka. Initially a conflict over individual title and collective land ownership, all-out war broke out and soon spread throughout the region. It was fought by more than 3,500 imperial troops brought in from Australia, as well as volunteer soldiers and militia, against Māori forces that fluctuated between a few hundred and about 1,500. Total losses among the imperial, volunteer and militia troops are estimated to have been 238, while Māori casualties totalled about 200, although the proportion of Māori casualties was higher.

The war ended in a ceasefire, with neither side explicitly accepting the peace terms of the other. Although there were claims by the British that they had won the war, there were widely held views at the time they had suffered an unfavourable and humiliating result. Historians have also been divided on the result. Historian James Belich has claimed that the Māori succeeded in thwarting the British bid to impose sovereignty over them, and had therefore been victorious. But he said the Māori victory was a hollow one, leading to the invasion of the Waikato.

In its 1996 report to the Government on Taranaki land claims, the Waitangi Tribunal observed that the war was begun by the Government, which had been the aggressor and unlawful in its actions in launching an attack by its armed forces. An opinion sought by the tribunal from a senior constitutional lawyer stated that the Governor, Thomas Gore Browne, and certain officers were liable for criminal and civil charges for their actions. Historian William Oliver has criticised this report claiming the tribunal ignores the constraints and political realities faced by the Crown while simultaneously taking into account the surrounding circumstances when judging the actions of the Taranaki Maori. The term "First Taranaki War" is opposed by some historians, who refer only to the Taranaki Wars, rejecting suggestions that the post-1861 conflict was a second war. The 1927 Royal Commission on Confiscated Land also referred to the hostilities between 1864 and 1866 as a continuation of the initial Taranaki war.

The catalyst for the war was the disputed sale of 600 acres (2.4 km²) of land known as the Pekapeka block, or Teira's block, at Waitara. The block's location perfectly suited European settlers' wish for a township and port to serve the north of the Taranaki district and its sale was viewed as a likely precedent for other sales that would open up for settlement all land between New Plymouth and the Waitara River. Pokikake Te Teira Manuka, a minor chief of the Te Atiawa iwi, first offered the land to the New Zealand government in 1857, immediately attracting vehement opposition from the paramount chief of the tribe, Wiremu Kīngi, who declared a veto on the plan. Kingi initially claimed that the land was collectively owned and therefore Teira did not have the right to sell the land, but later admitted Teira and his family were the sole owners of the land and that he simply didn't want the land to be disturbed. Teira's sale was, however, supported by Ihaia Kirikumara and his brother Tamati, who wrote letters to newspapers claiming that European occupation would allow returned slaves to live in security and lessen the chance that Waikato war parties would return.

Governor Browne felt obliged to resist the veto; he insisted Māori had the right to sell if they wished, and wanted to demonstrate support for a friendly chief over an individual who was resisting the Crown's authority and the expansion of European law. Browne accepted the purchase with full knowledge of the circumstances and tried to occupy the land, anticipating it would lead to armed conflict. A year earlier Browne had written to the Colonial Office in England, advising: "I have, however, little fear that William King (Kingi) will venture to resort to violence to maintain his assumed right, but I have made every preparation to enforce obedience should he presume to do so."

Although the pressure for the sale of the block resulted from the colonists' hunger for land in Taranaki, the greater issue fueling the conflict was the Government's desire to impose British administration, law and civilisation on Māori as a demonstration of the substantive sovereignty the British believed they had gained in the 1840 Treaty of Waitangi. The hastily written Māori translation, however, had given Māori chiefs an opposing view that the English had gained only nominal sovereignty, or "governorship" of the country as a whole while Māori retained "chieftainship" over their lands, villages and treasures.

By 1860, it was tacitly recognised that British law prevailed in the settlements and Māori custom elsewhere, though the British, who by then outnumbered Māori, were finding this increasingly irksome. One commentator observed, concerning Waitara: "We seem to be fast approaching a settlement of that point, whether Her Fair Majesty or His Dark Majesty shall reign in New Zealand." The British were convinced that their system represented the best that civilization had to offer and saw it as their duty and right to impose it on other peoples.