The following year, Cameron was appointed commander of British forces in New Zealand, which was dealing with the ongoing New Zealand Wars. At the time, the Colonial Government was engaged in a conflict with the Māori in the Taranaki region. However, by the time Cameron arrived in the Taranaki, a truce had been arranged. Two years later, he suppressed a further outbreak of fighting in the area and then led the invasion of the Waikato to deal with the King Movement, a Māori resistance that threatened British sovereignty in the country. He commanded a series of mostly successful engagements with the Kingites, followers of the King Movement, but none were decisive. By March 1864, he had advanced in the Waikato heartland and had pushed the Kingites into the King Country. At Gate Pā in April 1864, his forces suffered a major defeat. By this stage, Cameron was becoming disillusioned with the conduct of the war. Against his wishes, in early 1865 he commanded a campaign against Māori in the southern Taranaki. Coming under political pressure to wage a war he felt was inappropriate, he tendered his resignation and left New Zealand in August 1865.