In mid-1846, Governor George Grey decided to neutralise the Ngāti Toa threat in the Wellington region by arresting Te Rauparaha. Despite the fact that he had encouraged Maori to leave the Hutt Valley, Grey did not trust Te Rauparaha to remain neutral. He believed that removing Te Rauparaha from the area would weaken Ngāti Toa and assert his authority over the chief’s mana. He also wanted to avoid forcing Te Rauparaha into a choice between his nephew and the settlers.
A small naval party landed at Te Rauparaha’s pā at Taupō (Plimmerton) at dawn on 23 July. The elderly chief appeared from his dwelling and grabbed a taiaha. His attempted blows were deflected, and he was seized and led away in chains to HMS Calliope. He was informed that he was under arrest for supplying weapons to Māori deemed to be in open rebellion against the Crown. No charges were actually laid and his continued detention was illegal. Te Rauparaha, like Te Kāeaea before him, was sent to Auckland. By the time he was released in January 1848, his mana and that of his tribe had diminished.
The British built a stockade not far from Te Rauparaha’s pā. The campaign to pacify the region now switched its focus to Te Rangihaeata and his positions in the nearby Pāuatahanui inlet.
When the British advanced on Te Rangihaeata’s pā at Pāuatahanui (where St Alban’s church stands today), the chief withdrew north to a position in the hills east of the Horokiri Stream. More than 300 Ngāti Toa, including women and children, took shelter behind a fortified position on a high ridgeline. The abandoned pā at Pāuatahanui was later turned into a British military post. It was garrisoned by detachments of regular regiments and provided protection to the Europeans who settled around the inlet.
The arrival of British reinforcements enabled an assault against Te Rangihaeata’s new position, now known as Battle Hill. The attack began on 6 August 1846 in freezing rain. The assault force consisted of 250 British soldiers as well as militia and police. They were joined by 150 Te Ātiawa led by Wiremu Kīngi Te Rangitāke, and 100 dissident Ngāti Toa whom the British distrusted.
The government force moved up close to Te Rangihaeata’s position but pulled back when three of their number were killed, including Ensign H.M. Blackburn. A frontal assault was considered but quickly dismissed by officers mindful of the disastrous attack at Ōhaeawai the previous winter. The terrain and vegetation prevented a flanking manoeuvre, and thousands of rounds of musket fire failed to make any impression.
On 7 August two small mortars were brought up to about a kilometre from the fortification. Approximately 80 shells were fired, many landing in or near Te Rangihaeata’s position. Reluctant to advance and fearful of a counter-attack, the British decided to withdraw their regular troops. From 10 August it was left to the Te Ātiawa warriors to launch an occasional raid. On the 13th it was discovered that Te Rangihaeata had slipped away under cover of darkness and rain.
Te Rangihaeata’s groups were pursued by their Māori foe. A long retreat into the neighbouring Horowhenua district, in appalling winter conditions, effectively ended the Hutt Valley campaign.
Eventually Te Rangihaeata settled in the Poroutawhao swamp, south of present-day Foxton. His people suffered great hardships over the next few years but generally did not obstruct further European settlement. The government chose to leave Te Rangihaeata alone, declining to take action even when he imposed tolls on travellers on the beach road between Foxton and Levin.
Te Rangihaeata died in November 1855.
The Wellington campaign claimed few lives. Its real significance was the reassurance it gave settlers that their needs were slowly but surely being met by the Crown. Coming so quickly after the conclusion of the fighting in the Far North, the pacification of Te Rauparaha and Te Rangihaeata did much to enhance Grey’s reputation with the settler population. Conflict in two key areas of European settlement had been resolved.