quality:correction
European settlement

Following the signing of the Treaty of Waitangi in February 1840, Lieutenant-Governor Captain William Hobson declared British sovereignty over New Zealand in May 1840 and the South Island, along with the rest of New Zealand, briefly became a part of the Colony of New South Wales. This declaration was in response to France's attempts to colonise the South Island at Akaroa and the New Zealand Company attempts to establish a separate colony in Wellington, and so Hobson declared British sovereignty over all of New Zealand on 21 May 1840 (the North Island by treaty and the South by discovery). Seven days after the declaration, the Treaty was signed at Akaroa on 28 May.

On 17 June 1843, Māori and British settlers clashed at Wairau in what became known as the Wairau Affray. Also known as the Wairau Massacre in most older texts, it was the first serious clash of arms between the two parties after the signing of the Treaty of Waitangi and the only one to take place in the South Island. Four Māori died and three were wounded in the incident, while among the Europeans the toll was 22 dead and five wounded. Twelve of the Europeans were shot dead or clubbed to death after surrendering to Māori who were pursuing them.

The Otago Settlement, sponsored by the Free Church of Scotland, took concrete form in Otago in March 1848 with the arrival of the first two immigrant ships from Greenock (on the Firth of Clyde) – the John Wickliffe and the Philip Laing. Captain William Cargill, a veteran of the Peninsular War, served as the colony's first leader: Otago citizens subsequently elected him to the office of Superintendent of the Province of Otago.

While the North Island was convulsed by the New Zealand Wars of the 1860s and 1870s, the South Island, with its low Māori population, was generally peaceful. In 1861, gold was discovered at Gabriel's Gully in Central Otago, sparking a gold rush. Dunedin became the wealthiest city in the country, and many in the South Island resented financing the North Island's wars.

In the 1860s, several thousand Chinese men, mostly from the Guangdong province, migrated to New Zealand to work on the South Island goldfields. Although the first Chinese migrants had been invited by the Otago Provincial government, they quickly became the target of hostility from white settlers and laws were enacted specifically to discourage them from coming to New Zealand.