The Second Taranaki War is a term used by some historians for the period of hostilities between Māori and the New Zealand Government in the Taranaki district of New Zealand between 1863 and 1866.

The term is avoided by some historians, who either describe the conflicts as merely a series of West Coast campaigns that took place between the Taranaki War (1860-1861) and Titokowaru's War (1868-69), or an extension of the First Taranaki War.The conflict, which overlaps the wars in Waikato and Tauranga, is fueled by a combination of factors: lingering Māori resentment over the sale of land at Waitara in 1860 and government delays in resolving the issue; a large-scale land confiscation policy launched by the government in late 1863; and the rise of the Hauhau movement, an extremist part of the Pai Marire syncretic religion, which is strongly opposed to the alienation of Māori land and eager to strengthen Māori identity.

The Hauhau movement becomes a unifying factor for Taranaki Māori in the absence of individual Māori commanders.The style of warfare after 1863 differs markedly from that of the 1860-61 conflict, in which Māori had taken set positions and challenged the army to an open contest.

From 1863 the army, working with greater numbers of troops and heavy artillery, systematically takes possession of Māori land by driving off the inhabitants, adopting a "scorched earth" strategy of laying waste to Māori villages and cultivations, with indiscriminate attacks on villages, whether warlike or otherwise.

As the troops advance, the Government builds an expanding line of redoubts, behind which settlers build homes and developed farms.

The effect is a creeping confiscation of almost a million acres of land, with little distinction between the land of loyal or rebel Māori owners.

The Government's war policy is opposed by the British commander, General Duncan Cameron, who clashes with Governor Sir George Grey and offers his resignation in February 1865.

He leaves New Zealand six months later.

Cameron, who views the war as a form of land plunder, had urges the Colonial Office to withdraw British troops from New Zealand and from the end of 1865 the Imperial forces begin to leave, replaced by an expanding New Zealand military force.

Among the new colonial forces are specialist Forest Ranger units, which embark on lengthy search-and-destroy missions deep into the bush.

The Waitangi Tribunal has argued that apart from the attack on Sentry Hill in April 1864, there was an absence of Māori aggression throughout the entire Second War, and that therefore Māori were never actually at war.

It concluded: "In so far as Māori fought at all – and few did – they were merely defending their kainga, crops and land against military advance and occupation."

(The Taranaki Report - Kaupapa Tuatahi, Waitangi Tribunal, chapter 4, 1996.)