In 1865 the mountain was confiscated from Māori by the New Zealand Government under the powers of the New Zealand Settlements Act 1863, ostensibly as a means of establishing and maintaining peace amid the Second Taranaki War. The legislation was framed with the intention of seizing and dividing up the land of Māori "in rebellion" and providing it as farmland for military settlers. In 1839 the mountain had been climbed by the Swiss trained doctor and naturalist Ernst Dieffenbach. During his initial ascent, he identified the fast-flowing streams as being well suited to water driven mills. Dieffenbach was employed by the New Zealand Company to advise on the potential of land he explored in the North Island in 1839–40.