The area around the mouth of the Whanganui was a major site of pre-European M?ori settlement. In the 1820s coastal tribes in the area assaulted the Kapiti Island of Ng?ti Toa chief Te Rauparaha. Te Rauparaha retaliated in 1830 sacking Putiki P? and slaughtering the inhabitants. The first European traders arrived in 1831, followed in 1840 by missionaries Octavius Hadfield and Henry Williams who collected signatures for the Treaty of Waitangi. After the New Zealand Company had settled in Wellington the company looked for more suitable places for settlers. Edward Wakefield, son of Edward Gibbon Wakefield, negotiated the sale of 40,000 acres in 1840. A town, originally known as Petre after Lord Petre, one of the Directors of the New Zealand Company, was established at the river mouth shortly after. The name was officially changed to Wanganui on 20 January 1854.
The early years of the new town were problematic. Purchase of land from the local tribes had been haphazard and irregular, and as such many M?ori were angered with the influx of P?keh? onto land that they still claimed. It was not until the town had been established for eight years that agreements were finally reached between the colonials and local tribes, and some resentment continued (and still filters through to the present day).
Wanganui grew rapidly after this time, with land being cleared for pasture. The town was a major military centre during the Land Wars of the 1860s, although local M?ori at Putikiremained friendly to the town's settlers. In 1871 a town bridge was opened followed six years later by the railway bridge at Aramoho. The town was linked by rail to both New Plymouth and Wellington by 1886.
Wanganui was incorporated as a Borough on 1 February 1872 and declared a city on 1 July 1924. Perhaps the city's biggest scandal happened in 1920, when the Mayor, Charles Mackay, shot and wounded a young poet, D'Arcy Cresswell, who had been blackmailing him over his homosexuality
